Download PWS-600 User Manual - Prairie Wind Systems

PWS-600
Data Logger
User’s Manual
14-10600
03/17/2014
PWS-600 User’s Manual
Copyright © 2014 by Prairie Wind Systems, LLC. All Rights Reserved.
No part of this document may be photocopied, reproduced, or translated to another language without
the prior written consent of Prairie Wind Systems.
The information contained in this document is subject to change without notice. Prairie Wind Systems
has made a reasonable effort to ensure that the information contained in this document is accurate as
of the date of publication.
Prairie Wind Systems makes no warranty of any kind with regards to this material, including, but not
limited to, its fitness for a particular application. Prairie Wind Systems will not be liable for errors
contained herein or for incidental or consequential damages in connection with the furnishing,
performance, or use of this material. In no event shall Prairie Wind Systems be liable for any claim for
direct, incidental, or consequential damages arising out of, or in connection with, the sale, manufacture,
delivery, or use of any product.
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PWS-600 User’s Manual
1
2
3
4
5
6
7
Regulatory Information......................................................................................................................... 6
1.1
FCC Statement............................................................................................................................... 6
1.2
Battery Statement......................................................................................................................... 6
Warranty and Assistance ...................................................................................................................... 7
Overview ............................................................................................................................................... 8
Specifications ........................................................................................................................................ 9
Installation .......................................................................................................................................... 13
5.1
Environmental Considerations.................................................................................................... 13
5.2
Mounting the Device................................................................................................................... 13
5.3
Connector Pin-Out ...................................................................................................................... 14
5.4
Terminal Block Accessory............................................................................................................ 15
5.5
Power Requirements .................................................................................................................. 16
5.6
Charging Requirements............................................................................................................... 16
5.7
Status Indicators ......................................................................................................................... 17
5.8
Communication ........................................................................................................................... 18
5.8.1
RS485 Signals ...................................................................................................................... 18
5.8.2
RS232 Signals ...................................................................................................................... 18
Getting Started.................................................................................................................................... 19
6.1
Device Configuration................................................................................................................... 19
6.2
Network Communication Settings .............................................................................................. 19
6.3
Site Identification ........................................................................................................................ 19
6.4
Configure the Sensor Networks .................................................................................................. 20
6.5
Configure the Data Log ............................................................................................................... 20
Register Map ....................................................................................................................................... 21
7.1
Device Configuration Registers ................................................................................................... 21
7.1.1
Register Map Version .......................................................................................................... 21
7.1.2
Device Id .............................................................................................................................. 21
7.1.3
Serial Number ..................................................................................................................... 21
7.1.4
Firmware Version ................................................................................................................ 21
7.1.5
Boot Code Version .............................................................................................................. 21
7.1.6
Hardware Version ............................................................................................................... 22
7.1.7
Site Id .................................................................................................................................. 22
7.1.8
Site Name ............................................................................................................................ 22
7.1.9
Site Information .................................................................................................................. 22
7.1.10 Device Address .................................................................................................................... 22
7.1.11 Low Voltage Warning Threshold ......................................................................................... 22
7.2
Device Command Register .......................................................................................................... 23
7.3
Device Status Registers ............................................................................................................... 25
7.3.1
Device Status ....................................................................................................................... 25
7.3.2
Ambient Temperature ........................................................................................................ 26
7.3.3
Input Voltage....................................................................................................................... 26
7.3.4
Charge Voltage .................................................................................................................... 26
7.3.5
Date and Time ..................................................................................................................... 26
7.4
Communication Configuration Registers .................................................................................... 27
7.4.1
Communication Settings ..................................................................................................... 27
7.4.2
Message Timeout ................................................................................................................ 28
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PWS-600 User’s Manual
7.4.3
Sleep Timeout ..................................................................................................................... 28
7.4.4
Message Counters............................................................................................................... 28
7.5
Sensor Networks ......................................................................................................................... 29
7.5.1
RS485 Smart Sensor Network ............................................................................................. 29
7.5.2
SDI-12 Smart Sensor Network............................................................................................. 35
7.5.3
Analog Sensor Network....................................................................................................... 37
7.5.4
Discrete Sensor Network .................................................................................................... 38
7.6
Data Log Configuration Registers................................................................................................ 39
7.6.1
Log Enable ........................................................................................................................... 40
7.6.2
Log Pause ............................................................................................................................ 40
7.6.3
Next Scheduled Record ....................................................................................................... 41
7.6.4
Log Interval.......................................................................................................................... 41
7.6.5
Log Offset ............................................................................................................................ 41
7.6.6
Number of Sensor Commands ............................................................................................ 41
7.6.7
Sensor Command Groups ................................................................................................... 42
7.6.8
MODBUS Command Group Format .................................................................................... 42
7.6.9
SDI-12 Command Group Format......................................................................................... 44
7.6.10 Analog Command Group Format ........................................................................................ 46
7.6.11 Discrete Command Group Format ...................................................................................... 49
7.6.12 Last Sensor Readings ........................................................................................................... 51
7.7
Switched Power Outputs ............................................................................................................ 52
7.7.1
Switched Output Status ...................................................................................................... 52
7.7.2
Switched Power Output Configuration ............................................................................... 53
7.8
Discrete Outputs ......................................................................................................................... 55
7.8.1
Discrete Output Status ........................................................................................................ 55
7.8.2
Discrete Output Configuration ............................................................................................ 55
7.9
Data Log Recording Registers ..................................................................................................... 57
7.9.1
Encryption Key .................................................................................................................... 57
7.9.2
Recording Data .................................................................................................................... 57
7.9.3
Recording Speed ................................................................................................................. 58
7.10 Data Log Retrieval Registers ....................................................................................................... 59
7.10.1 Data Log Size ....................................................................................................................... 59
7.10.2 Data Log Used ..................................................................................................................... 59
7.10.3 Lowest and Highest Record Numbers ................................................................................. 59
7.10.4 Download Record Count ..................................................................................................... 60
7.10.5 Record Number ................................................................................................................... 60
7.10.6 Record Size .......................................................................................................................... 60
7.10.7 Record Data......................................................................................................................... 60
7.10.8 Data Decryption .................................................................................................................. 61
7.10.9 Data Retrieval Procedure .................................................................................................... 61
7.10.10 Data Log Download Command ........................................................................................... 61
7.10.11 Last Data Log Record........................................................................................................... 63
7.11 Sensor Network Pass-Through Registers .................................................................................... 64
7.11.1 Sensor Network................................................................................................................... 64
7.11.2 MODBUS Protocol Pass-Through ........................................................................................ 64
7.11.3 SDI-12 Protocol Pass-Through............................................................................................. 64
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PWS-600 User’s Manual
7.12 Password Security Registers ....................................................................................................... 66
7.12.1 Security Password ............................................................................................................... 66
7.12.2 Login Password ................................................................................................................... 66
7.13 Diagnostic Registers .................................................................................................................... 67
7.13.1 Configuration Flash Writes.................................................................................................. 67
7.13.2 Last Reset Type ................................................................................................................... 67
7.13.3 Fault Information ................................................................................................................ 68
7.13.4 High and Low Temperatures ............................................................................................... 68
7.13.5 Data Log Chip Id .................................................................................................................. 68
7.13.6 Data Log Erasure Count....................................................................................................... 68
8 MODBUS Protocol ............................................................................................................................... 69
8.1
RTU Transmission Mode ............................................................................................................. 69
8.1.1
RTU Character Format ........................................................................................................ 69
8.1.2
RTU Message Format .......................................................................................................... 70
8.2
ASCII Transmission Mode............................................................................................................ 70
8.2.1
ASCII Character Format ....................................................................................................... 70
8.2.2
ASCII Message Format ........................................................................................................ 71
8.3
MODBUS IP ................................................................................................................................. 72
8.4
Device Addressing ....................................................................................................................... 72
8.5
Data Types................................................................................................................................... 72
8.5.1
USHORT: Unsigned Short ................................................................................................... 72
8.5.2
SHORT: Signed Short .......................................................................................................... 73
8.5.3
ULONG: Unsigned Long ...................................................................................................... 73
8.5.4
LONG: Signed Long ............................................................................................................. 73
8.5.5
FLOAT: Floating Point ......................................................................................................... 73
8.5.6
STRING: Character String ................................................................................................... 74
8.5.7
TIME: Date and Time .......................................................................................................... 74
8.6
Function Codes............................................................................................................................ 75
8.6.1
Report Slave Id .................................................................................................................... 75
8.6.2
Read Registers ..................................................................................................................... 75
8.6.3
Write Multiple Registers ..................................................................................................... 77
8.6.4
Write Single Register ........................................................................................................... 78
8.6.5
Exception Response ............................................................................................................ 79
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PWS-600 User’s Manual
1 Regulatory Information
The PWS-600 has been tested and approved to be compliant to the following regulatory standards.




EN61326-1: 2006, for immunity in industrial locations (CE)
EN55011: 2009, Class A, Group 1, for emissions (CE)
CISPR 11, Ed. 5.0, 2009-05, Class A, Group 1, for emissions
CFR Title 47: FCC Part 15, Class A, for emissions
Any changes or modifications not expressly approved by the party responsible for compliance could void
the user's authority to operate the equipment.
1.1 FCC Statement
This device has been tested and found to comply with the limits for a Class A digital device, pursuant to
part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful
interference when the equipment is operated in a commercial environment. This device generates, uses
and can radiate radio frequency energy and, if not installed and used in accordance with this manual,
may cause harmful interference to radio communications. Operation of this device in a residential area
is likely to cause harmful interference in which case the user will be required to correct the interference
at his own expense.
1.2 Battery Statement
This device contains a poly-carbonmonoflouride lithium coin cell battery to preserve the real-time clock
when power is not applied. The Department of Transportation requires that the outside of each
package that contains primary lithium batteries, regardless of the size or number of batteries, be labeled
with the following statement: “PRIMARY LITHIUM BATTERIES – FORBIDDEN FOR TRANSPORT ABOARD
PASSENGER AIRCRAFT”. The labeling requirement covers shipping via highway, rail, vessel or cargo-only
aircraft and covers all shipments into or out of the United States. The label must be in contrasting color
and the letters must be 12 mm (0.5 in) in height for packages weighing more than 30 Kg and 6 mm (0.25
in) in height for packages weighing less than 30 Kg.
The lithium battery does not contain enough lithium to qualify as a reactive hazardous waste. The
battery is safe for disposal in the normal municipal waste stream.
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PWS-600 User’s Manual
2 Warranty and Assistance
The PWS-600 is warranted by Prairie Wind Systems, LLC to be free from defects in materials and
workmanship under normal use and service for twelve (12) months from the date of shipment unless
specified otherwise. Prairie Wind Systems’ obligation under this warranty is limited to repairing or
replacing, at Prairie Wind Systems’ option, defective products. The customer shall assume all costs of
removing, reinstalling, and shipping defective products to Prairie Wind Systems. Prairie Wind Systems
will return such products by surface carrier prepaid. This warranty shall not apply to any product which
has been subjected to modification, misuse, neglect, accidents of nature, or shipping damage. This
warranty is in lieu of all other warranties, expressed or implied, including warranties of merchantability
or fitness for a particular purpose. Prairie Wind Systems is not liable for special, indirect, incidental,
or consequential damages.
Products may not be returned without prior authorization. To obtain a Returned Materials
Authorization (RMA) number, contact Prairie Winds Systems at the phone number below. Please write
the RMA number clearly on the outside of the shipping container. Prairie Wind Systems’ shipping
address is:
Prairie Wind Systems, LLC
RMA #____________
7784 Big Sky Court
Windsor, CO 80550
Phone: 970.460.6066
Fax: 970.692.2434
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PWS-600 User’s Manual
3 Overview
The PWS-600 is a MODBUS slave device that periodically polls and logs data from a wide variety of
analog, discrete, and smart sensors. The current readings from the sensors are available to the
MODBUS master device via a block of MODBUS holding registers.
Readings are polled and logged at the programmed rate and are automatically time-stamped and checksummed. When the memory is full, recording automatically wraps around to record the newest data
over the oldest data. All data are stored in non-volatile flash memory which does not require power for
data retention. Standard write and read register commands are used to extract logged data from the
device.
In addition to the data logging feature, the PWS-600 extends the capabilities of a system with these
additional features.

Data can be recorded and retrieved securely using the Advanced Encryption Standard with a
user-defined key.

The PWS-600 includes an accurate, temperature-compensated, real-time clock. Every data
record is date and time stamped. Polling and logging are synchronized to the real-time clock,
making it easy to align data collection across multiple systems.

The PWS-600 includes a built-in solar charge controller compatible with standard 12 volt sealed
lead-acid batteries, reducing a system’s overall cost and complexity.

The device’s ambient temperature and input voltages are logged with every data record for
enhanced data tracking and system troubleshooting, particularly in battery operated systems.
The user can track battery and recharging performance in standalone and solar charged
systems.
The Prairie View Software that comes with the device provides a convenient means to configure the
device and manage its data log.
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PWS-600 User’s Manual
4 Specifications
Case
Description
ABS plastic with integral mounting flanges
Dimensions
6.62”L x 3.30”W x 1.30”H (16.8 x 8.4 x 3.3 cm) including flanges and connector
Weight
6.1 oz (173.6 g)
Ratings
IP 66 and NEMA 4X
Connector
44-pin D-sub socket
Environmental
Operating Temperature -40 to 70 °C (-40 to 158 °F)
Operating Humidity
5 to 95 %RH non-condensing
Storage Temperature
-40 to 80 °C (-40 to 176 °F)
Battery Input
Input Voltage
8 to 32 Vdc
Transient Protection
250 Watts Peak
Sleep Current
< 500 µA typical at 13.5 Vdc, RS485 and RS232 networks inactive
Idle Current
500 µA typical at 13.5 Vdc, RS485 and RS232 networks inactive
Active Current
30 mA typical at 13.5 Vdc, not including sensor load currents
Battery Charge Controller
Input Voltage
15 to 32 Vdc
Transient Protection
250 Watts Peak
Battery Rating
12 Vdc, 2.3 to 7.0 Ahr, Sealed Lead-Acid
Peak Charge Current
1A
Charging Temperature
-15 to 45 °C (5 to 115 °F) charging disabled outside of this range
MODBUS RS485 Transceiver
Unit Load
1/8
Termination
None
Common Mode Range
+/- 7 Vdc
Transient Protection
250 Watts Peak
Protocol
Half-Duplex, MODBUS over Serial Line
Transmission Modes
RTU, ASCII, IP
Addressing
1 to 247 plus broadcast
Baud Rates
1200, 2400, 4800, 9600, 19200, 38400, 57600
Data Bits
7, 8
Parity
Odd, Even, None
Stop Bits
1, 2
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PWS-600 User’s Manual
MODBUS RS232 Transceiver
Type
9-pin DTE (data terminal equipment)
Port Power
Switched, +5V, 275 mA
Input Voltage Swing
+/- 25 Vdc absolute maximum
Output Voltage Swing
+/- 5 Vdc minimum
ESD Protection
+/- 15 kV
Protocol
Half-Duplex, MODBUS over Serial Line
Transmission Modes
RTU, ASCII, IP
Addressing
1 to 247 plus broadcast
Baud Rates
1200, 2400, 4800, 9600, 19200, 38400, 57600
Data Bits
7, 8
Parity
Odd, Even, None
Stop Bits
1, 2
Smart Sensor RS485 Port
Unit Load
1/8
Termination
4.75K ohm polarity terminations
Common Mode Range
+/- 7 Vdc
Transient Protection
250 Watts Peak
Protocol
Half-Duplex, MODBUS over Serial Line or SDI-12
Transmission Modes
RTU, ASCII
Addressing
1 to 247 plus broadcast
Baud Rates
1200, 2400, 4800, 9600, 19200, 38400, 57600
Data Bits
7, 8
Parity
Odd, Even, None
Stop Bits
1, 2
Smart Sensor SDI-12 Port
SDI Version
1.3
Data Line
Bidirectional, tri-state, 5V logic
Transient Protection
250 Watts Peak
Analog Voltage Sensor Inputs
Inputs
6 single-ended or 3 differential
Single-ended Ranges
0 to 5000, 0 to 2000, 0 to 1000, 0 to 500 mVdc
Differential Ranges
±2000, ±1000, ±500, ±250, ±125, ±60, ±30 mVdc
Resolution
0.002 %FS
Accuracy
±0.05% of reading ±0.01 %FS over operating temperature range
Voltage Excitation
4.096 Vdc ±0.05%, 30 mA maximum
Resistive Excitation
3900 ohms ±0.15%, connected to the voltage excitation
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PWS-600 User’s Manual
Current Loop Terminations
Terminations
2
Range
0 to 20 mA
Resolution
0.0003 mA
Accuracy
±0.3% of reading ±0.002 mA
Loop Compliance
1 Vdc at 20 mA
RTD Termination
RTD Type
Pt1000
Range
-50 to 200 °C
Resolution
0.1 °C
Accuracy
±1 °C ± RTD accuracy
Discrete Input/Outputs
Channels
2
Input/Output Voltage
0 to 32 Vdc
Input High Threshold
2.5 Vdc
Input Low Threshold
2.0 Vdc
Input Modes
State, Switch Closure, Pulse Count, Frequency
Switch Closure Freq.
100 Hz maximum
Pulse Count
65535 pulses per record
Frequency Input
65 kHz maximum, ±0.02% of reading ±1 Hz
Output Type
Open collector
Output Current
500 mA maximum
Output Modes
Remote On/Off, High Alarm, Low Alarm
Switched Power Ports
Ports
2 switched battery
Output Current
500 mA maximum
Modes
Remote On/Off, Scheduled On/Off, On During Measure
Data Storage
Memory Type
4 MB non-volatile flash
Data Record Size
1 to 64 registers (2 to 128 bytes)
Number of Data
131,008 (1 register per record, no encryption)
Records
to 25,216 (64 registers per record, with encryption)
Recording Rate
1 record per second with no wraparound
1 record per 5 seconds after wraparound
Recording Endurance
50,000 wraparound and erase cycles
Data Security
AES-128 Advanced Encryption Standard
Data Retention
10 years
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PWS-600 User’s Manual
Real-Time Clock
Resolution
Accuracy
Backup Battery Life
Temperature Sensor
Resolution
Accuracy
Voltage Sensor
Resolution
Accuracy
0.01 seconds
+/- 1 minute per month, temperature compensated
10 years
0.1 °C
+/- 3 °C
0.01 Vdc
+/- 0.05 Vdc
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PWS-600 User’s Manual
5 Installation
5.1 Environmental Considerations
The PWS-600 is specified for operation in a non-condensing humidity environment. When temperature
and/or humidity tolerances are exceeded, damage to internal components and/or measurement
inaccuracies due to condensation may result.
The device must be housed in an enclosure suited for field use. The environmental ratings of the
device’s enclosure are intended as a backup to the primary field housing. The field housing should
contain desiccant that is replaced or dried frequently enough to control the humidity. Effective control
of the humidity is the user’s responsibility.
Caution: If the battery charger is used, the field enclosure must be vented so that charge gasses
from the battery do not accumulate. Failure to do so may present a risk of explosion.
5.2 Mounting the Device
Mounting flanges are integral to the device’s enclosure. Six mounting holes sized for #4 screws are
provided. Two or more screws should be used to mount the enclosure.
6.62” (16.81 cm)
3.30”
(8.38 cm)
2.78”
(7.06 cm)
6.10” (15.49 cm)
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PWS-600 User’s Manual
5.3 Connector Pin-Out
The PWS-600 uses a standard 44-pin D-subminiature socket. The sockets on the face of the connector
are numbered as shown below. This is also the pin-out looking at the wiring side of the mating 44-pin Dsub plug.
The function of each pin is described in the following table.
Pin
Name
Description
1
CTS
RS232 CTS output to pin 8 of a 9-pin D-sub plug
2
DTR
RS232 DTR input from pin 4 of a 9-pin D-sub plug
3
GND
RS232 GND to pin 5 of a 9-pin D-sub plug
4
CHG+
Positive side of solar panel charge input (parallel with pin 19)
5
CHGNegative side of solar panel charge input (parallel with pin 20)
6
BAT+
Positive side of battery or power input (parallel with pin 21)
7
BATNegative side of battery or power input (parallel with pin 22)
8
SWBAT1
Switched power output 1 (parallel with pin 23)
9
SWBAT2
Switched power output 2 (parallel with pin 24)
10
DIO1
Discrete input/output port 1
11
DIO2
Discrete input/output port 2
12
LED_OK
Active low 10 mA constant current LED driver for OK status
13
LED_CHG
Active low 10 mA constant current LED driver for charge status
14
LED_LOW
Active low 10 mA constant current LED driver for low voltage status
15
LED_LOG
Active low 10 mA constant current LED driver for log/scan status
16
TXD
RS232 TXD input from pin 3 of a 9-pin D-sub plug
17
RXD
RS232 RXD output to pin 2 of a 9-pin D-sub plug
18
DCD
RS232 DCD output to pin 1 of a 9-pin D-sub plug
19
CHG+
Positive side of solar panel charge input (parallel with pin 4)
20
CHGNegative side of solar panel charge input (parallel with 5)
21
BAT+
Positive side of battery or power input (parallel with pin 6)
22
BATNegative side of battery or power input (parallel with pin 7)
23
SWBAT1
Switched power output 1 (parallel with pin 8)
24
SWBAT2
Switched power output 2 (parallel with pin 9)
25
SDI-12 DATA
SDI-12 smart sensor network data line
26
VEX
Analog excitation voltage output
27
REX
Analog excitation resistor output
28
AIN5
Analog input 5
29
AIN3
Analog input 3
30
AIN1
Analog input 1
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PWS-600 User’s Manual
Pin
31
32
33
34
35
36
37
38
39
40
41
42
43
44
Name
RTS
DSR
RI/5V
WAKE
RS485ARS485B+
SEN485ASEN485B+
LOOP2
LOOP1
AGND
AIN6
AIN4
AIN2
Description
RS232 RTS input from pin 7 of a 9-pin D-sub plug
RS232 DSR output to pin 6 of a 9-pin D-sub plug
RS232 RI input/5V switched output to pin 9 of a 9-pin D-sub plug
WAKE input
Master side RS485A- network input/output
Master side RS485B+ network input/output
Smart sensor RS485A- network input/output
Smart sensor RS485B+ network input/output
Current loop 2 resistor termination to GND
Current loop 1 resistor termination to GND
Analog ground reference
Analog input 6
Analog input 4
Analog input 2
For reliability of the connection, the mating connector should utilize the mounting standoffs provided.
The cable length should be kept as short as practical. The maximum length of cable for an RS485
network is 4000 feet (1200 meters). The maximum length of cable for an SDI-12 network is 200 feet (60
meters).
5.4 Terminal Block Accessory
The optional PWS-600T Terminal Block accessory board attaches to the 44-pin connector of the PWS600 and provides terminal block connections for wiring all signals.
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PWS-600 User’s Manual
5.5 Power Requirements
The wide battery input voltage range of the PWS-600 permits operation on a 12 volt or 24 volt DC
supply. The device will automatically shut down if the battery input voltage falls below 7 volts and will
resume normal operation when the input voltage rises above 8 volts. Sustained operation above 32
volts will damage the device. The input is reverse polarity and transient protected. Connect the positive
side of the battery or supply to the BAT+ terminal. Connect the negative side of the battery or supply to
the BAT- terminal.
Caution: SDI-12 sensors generally do not operate across the same wide input voltage range as
the PWS-600. The SDI-12 specification calls for a 12 volt DC supply that operates between 9.6
and 16 volts. Failure to observe the input voltage limits of a sensor can result in permanent
damage to the sensor and/or the PWS-600.
5.6 Charging Requirements
The PWS-600 contains a built-in charge controller for charging a 12 volt sealed lead acid (SLA) battery
rated between 2.3 and 7.0 amp-hours.
Caution: Attempting to charge any battery type other than a 12 volt sealed lead acid battery
may present an explosion hazard.
Caution: Attempting to charge an SLA battery rated less than 2.3 amp-hours may cause the
maximum battery charge current to be exceeded which can damage the battery and may
present an explosion hazard.
Caution: If the battery charger is used, the field enclosure must be vented so that charge gasses
from the battery do not accumulate. Failure to do so may present a risk of explosion.
Attempting to charge an SLA battery rated greater than 7.0 amp-hours may not fully charge the battery,
reducing the battery life and leaving the system susceptible to brown-out conditions.
The charge controller is optimized for use with a solar panel in the 10 watt range with a 15 to 32 volt
output; however, any comparable DC source, such as a mains connected DC power supply, can be used.
Connect the positive side of the solar panel or charging supply to the CHG+ terminal. Connect the
negative side of the solar panel or charging supply to the CHG- terminal.
If the charging feature is not required, the CHG terminals should be left unconnected. It is not
recommended to use the charger without a battery – if a DC power supply is being used instead of a
battery, it should be connected to the BAT terminals and the CHG terminals left unconnected. This will
result in the lowest possible power consumption.
The charger input is reverse polarity and transient protected; however, sustained operation above 32
volts will damage the device. The charger output is protected against a reversed battery and battery
voltages higher than 12 volts.
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PWS-600 User’s Manual
5.7 Status Indicators
The PWS-600 provides four system status indicators. The PWS-600T terminal block provides colored
LED indicators. When power is applied to the device, all indicators will light in sequence as a lamp test.
The status is then displayed for 30 seconds, after which the indicators are turned off to conserve power.
Press the WAKE button to display the status for an additional 30 seconds.
Note: Jumper the WAKE terminal to GND to display status continuously. This can be useful in an
industrial setting when power consumption is less of a concern, or when troubleshooting power
problems.
Three of the LED indicators provide power supply status as shown below.



ON: battery input above low threshold
OFF: battery input below low threshold
OFF: no charge input detected
OFF: no charge input detected
OFF: battery input above low threshold
ON: battery input below low threshold
ON: battery input above low threshold
ON: battery input above low threshold
FLASHING: battery is charging
ON: battery is charged
OFF: no charge faults
OFF: no charge faults
ON: battery input above low threshold
OFF: battery input below low threshold
ON: charge voltage detected
ON: charge voltage detected
ON: charging fault
ON: charging fault



charge input too low
temperature outside charge range
battery is not accepting charge
17
charge input too low
temperature outside charge range
battery is not accepting charge
PWS-600 User’s Manual
The blue LED indicates the logging state of the device as shown below.
OFF: Logging is disabled. The LED will pulse ON when a manual scan of the sensors is triggered.
ON: Logging is enabled. The LED will pulse OFF when a log scan of the sensors triggered.
FLASHING: Logging has been paused for a preset amount of time.
5.8 Communication
Communication with the data logger is done using the MODBUS serial line protocol over the RS485 or
RS232 interface. The device is preconfigured with the MODBUS standard settings of 19200 baud, 8 data
bits, even parity, 1 stop bit, RTU transmission mode, and device address 1.
5.8.1 RS485 Signals
RS485 communication is done using signals on terminal block TB10 labeled “PLC”. Three signals are
required to be connected to the master device: 485B+ is the positive transceiver signal, 485A- is the
negative transceiver signal, and GND is the ground reference. No termination resistor is provided
internally. In most applications, no termination resistor is necessary. If required, a resistor may be
added externally. The maximum offset of the transceiver signals from GND 7 volts. Both signals are
transient protected.
5.8.2 RS232 Signals
RS232 communication is done using the 9-pin D-sub connector labeled “MODEM/PLC”. Connection to a
PC or equivalent device requires the use of a null modem cable. Connection to a modem requires a
regular straight-through cable.
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PWS-600 User’s Manual
6 Getting Started
The PWS-600 communicates as a slave device using the industry standard MODBUS protocol for serial
devices. This section provides guidelines to getting the device up and running. If the device is not
already wired, follow the installation instructions provided in the previous section.
Section 7 describes the device register map. The PWS-600 uses the MODBUS Holding Registers data
model exclusively. All of the device functionality is accessed using the MODBUS read and write holding
register commands.
Section 8 provides the details of the MODBUS protocol for users that are not familiar with MODBUS.
Also refer to Section 8 for device-specific implementation information, such as the organization of
registers into data types.
6.1 Device Configuration
Configuring the device consists of writing user-specific settings to one or more of the device registers.
The Prairie View Software supplied with the device provides a convenient, step-by-step means to
configure the device and is the recommended place to start. Refer to the software manual for
instructions on installing the software on your desktop computer, laptop computer, or mobile device. It
is also possible to configure the device by directly writing to the registers using a master device with
pass-through capability, or using a third-party software tool.
6.2 Network Communication Settings
Before the device is placed on an active RS485 network, it must be configured to match the network’s
communication settings and be assigned a unique device address. The device is preconfigured with the
MODBUS standard settings of 19200 baud, 8 data bits, even parity, 1 stop bit, RTU transmission mode,
and device address 1. Refer to the Device Configuration section of the device register map to change
the device address. Refer to the Communication Configuration Registers section of the device register
map if any of the communication settings need to be changed.
6.3 Site Identification
If the user is collecting data from multiple devices located at different sites, it is recommended that the
Site Id register be written with a unique value for each site. The Site Id is recorded with every data
record, making it easier to track the data once it has been retrieved from a device.
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PWS-600 User’s Manual
6.4 Configure the Sensor Networks
Refer to section 7.5 to configure the sensor networks to match the sensor requirements. The Prairie
View software helps to automate this process; however, the configuration registers can also be written
directly using third-party software tools.
6.5 Configure the Data Log
The data log configuration registers must be programmed so that the PWS-600 will know how to acquire
data from the sensors and at what interval, refer to section 7.6. The Prairie View software helps to
automate this process; however, the configuration registers can also be written directly using thirdparty software tools.
Once the log is configured, set the Log Enable register to one to start logging. Data is then acquired and
logged at the specified interval. The most recent acquisition from the sensors is available in the data log
polling registers.
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PWS-600 User’s Manual
7 Register Map
The PWS-600 uses the MODBUS Holding Registers data model exclusively. All of the device functionality
is accessed using the MODBUS read and write holding register commands. The organization of the
register map is kept consistent among Prairie Wind System devices as much as practical.
7.1 Device Configuration Registers
The device configuration registers identify the device, its site location, and its basic configuration.
Device Configuration Registers
Register
Number
1000
1001
1002
1004
1005
1006
1007
1008
1024
1056
1057
Size
(Registers)
1
1
2
1
1
1
1
16
32
1
1
Data
Type
USHORT
USHORT
ULONG
USHORT
USHORT
USHORT
USHORT
STRING
USHORT
USHORT
USHORT
Access
R
R
R
R
R
R
R/W
R/W
R/W
R/W
R/W
Name
Register Map Version
Device Id
Serial Number
Firmware Version
Boot Code Version
Hardware Version
Site Id
Site Name
Site Information
Device Address
Low Voltage Warning Threshold
Default
Value
2
600
0
0
0
1
9600 mV
7.1.1 Register Map Version
This is the version of the register map supported by the device. This provides for the modification of the
register map at a future date and detection of the difference by the master device.
7.1.2 Device Id
This is the model number of the device. It can be used to validate the system configuration and to
identify the available feature set.
7.1.3 Serial Number
This is the serial number of the device. The master device can read the serial number of the device to
provide system traceability.
7.1.4 Firmware Version
This register identifies the firmware version of the device.
7.1.5 Boot Code Version
This register identifies the boot code version of the device. The boot code supports field upgrades of
the device firmware. The boot code on a given device will not change with firmware upgrades. Its
version is made available to support field upgrade utilities.
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PWS-600 User’s Manual
7.1.6 Hardware Version
This register contains the hardware version of the device.
7.1.7 Site Id
The Site Id is a general-purpose, non-volatile, read/write register. The contents of this register are
recorded with each logged data record, permitting data to be traced to a particular site or system.
7.1.8 Site Name
The Site Name identifies the site to a user. The 16-register, non-volatile string holds up to 32 characters.
7.1.9 Site Information
Site Information is comprised of 32, general-purpose, non-volatile, read/write registers. Use these
registers to hold system configuration and/or calibration data. The format of the data contained in the
registers is defined by the user. They can be used as individual registers or combined to form ULONG,
FLOAT or STRING data types. These registers should not be used to hold data that changes frequently.
7.1.10 Device Address
The device address is used to address the PWS-600 on the MODBUS network. The valid range for the
device address is 1 to 247. The default value is 1. When this register is written, the response will be
returned with the previous address. All subsequent commands must be sent with the new address. The
register is non-volatile. The address is used on both the RS485 and RS232 interfaces.
7.1.11 Low Voltage Warning Threshold
If the battery input voltage to the device is less than or equal to this threshold, the low voltage warning
status bit is set in the device status register. The threshold is set in millivolts and can range from 8000 to
32000 mV (8 to 32 volts). Attempting to write a value outside this range will generate an exception
response with the ILLEGAL WRITE VALUE exception code. This threshold also used by the LED indicators
to alert the user to a low battery.
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7.2 Device Command Register
The device command register is used to issue commands to the device. The register is isolated from
other registers in the register map to help prevent accidental writing.
Device Command Register
Register
Number
1065
Size
(Registers)
1
Data
Type
USHORT
Access
R/W
Name
Device Command
Default
Value
0
Writing a value shown in the following table will issue the corresponding device command. Attempting
to write any other value will generate an exception response with the ILLEGAL WRITE VALUE exception
code. Reading the register always returns zero.
Device Commands
Value
56573 (0xDCFD)
Name
Factory Defaults
56557 (0xDCED)
Erase Data Log
56541 (0xDCDD)
Download Data Log
56320 (0xDC00)
Security Mode
56480 (0xDCA0)
Read Sensors
Description
Resets device configuration registers to their factory default
values. The encryption key is erased and encryption is
disabled. Does not affect the communication settings, the
data log or the diagnostic registers. This command is not
allowed while data logging is enabled.
Erases the data log. Data cannot be recovered after issuing
this command. The response message is sent after erasure
is complete. Typical response time is 30 seconds. The
maximum response time is 90 seconds. Erasing the data log
does not affect the current encryption key. This command
is not allowed while data logging is enabled.
Starts the fast data download process. The maximum
response time to this command is 1000 milliseconds. Refer
to the Data Retrieval Registers section for a description of
the command.
Places the device in the security mode, requiring a master
device to log in with a password to regain access. The
command has no effect if password security is disabled.
Causes the PWS-600 to read data from its sensors
immediately using the command sequence currently
specified for data logging. Sensor values are placed in the
last sensor reading registers but are not logged. The device
status register should be monitored to determine when
sensor values are valid.
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PWS-600 User’s Manual
Device Commands (continued)
Value
56481 (0xDCA1)
Name
SDI-12 Command
56482 (0xDCA2)
SDI-12 over RS485
Command
56482 (0xDCA2)
Clear Sensor
Diagnostics
Description
Sends the command contained in the SDI-12 pass-through
registers to a sensor located on the SDI-12 network. The
data log must be disabled or paused in order to use this
command.
Sends the command contained in the SDI-12 pass-through
registers to a sensor located on the SDI-12 network. The
data log must be disabled or paused in order to use this
command.
Clears sensor network message counters.
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PWS-600 User’s Manual
7.3 Device Status Registers
The device status registers allow the master device to obtain the current operating status of the device.
Device Status Registers
Register
Number
1070
1071
1072
1073
1074
Size
(Registers)
1
1
1
1
4
Data
Type
USHORT
SHORT
USHORT
USHORT
TIME
Access
R/W
R
R
R
R/W
Name
Device Status
Ambient Temperature
Input Voltage
Charge Voltage
Date and Time
Default
Value
0
°C x 10
mV
0 mV
UTC
7.3.1 Device Status
This register contains device operational status. Each bit in the register represents a status value as
defined in the following table.
Device Status Register
Bit
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Mask
0x0001
0x0002
0x0004
0x0008
0x0010
0x0020
0x0040
0x0080
0x0100
0x0200
0x0400
0x0800
0x1000
0x2000
0x4000
0x8000
Name
Power Outage
Low Voltage
Clock Battery
Clock Fault
Clock Adjusted
Device Fault
Temperature
Sensor Busy
Encryption Enabled
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Description
A power outage caused a hardware reset and recovery
The input voltage is below the warning threshold
Timekeeping backup battery is low
Timekeeping restarted at 2000-01-01 00:00:00.00
Date and Time were changed
A device fault caused a reset and recovery
Device operating temperature range was exceeded
Sensor command sequence is busy (new values are not valid)
Encryption key is non-zero, data records will be encrypted
Always returns 0
Always returns 0
Always returns 0
Always returns 0
Always returns 0
Always returns 0
Always returns 0
The status register is non-volatile: information is retained across a power outage. The status represents
events that occurred since the last time the register was cleared. The device status is recorded with
each logged data record. The status register can be cleared at any time by writing zero to it. Any
conditions that persist or reoccur after being cleared will cause those bits to be set again. Attempting to
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PWS-600 User’s Manual
write any value other than zero to clear the register will generate an exception response with the
ILLEGAL WRITE VALUE exception code.
7.3.2 Ambient Temperature
This register measures and returns the ambient temperature in degrees Celsius (°C) multiplied by 10.
For example, an ambient temperature of 23.7 °C will be read as 237.
7.3.3 Input Voltage
This register measures and returns the battery input voltage applied to the device in millivolts (mV). For
example, a battery input voltage of 13.54 volts will be read as 13540.
7.3.4 Charge Voltage
This register measures and returns the charging voltage applied to the device in millivolts (mV). For
example, a charge input voltage of 19.76 volts will be read as 19760.
7.3.5 Date and Time
These registers hold the current date and time as a TIME data type. The device is programmed to
Universal Coordinated Time (UTC) at the factory and generally does not need to be adjusted. If the clock
should require adjustment, it is recommended that UTC continue to be used as the clock does not
provide for automatic adjustments for local Daylight Savings Time. The time stamps of stored data may
be post-processed to any local time as needed for reporting or analysis.
When setting the clock, the year must be in the range 2000 to 2399. Leap years in this range are
correctly handled. Attempting to write an invalid date or time will generate an exception response with
the ILLEGAL WRITE VALUE exception code. Setting the clock will clear the clock fault bit and set the
clock adjusted bit in the status register.
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PWS-600 User’s Manual
7.4 Communication Configuration Registers
These registers specify the communication configuration of the master RS485 and RS232 ports.
Register
Number
1101
1102
1103
1104
1105
1106
Size
(Registers)
1
1
1
1
1
1
Communication Configuration Registers
Data
Type
Access
Name
USHORT
R/W
Communication Settings
USHORT
R/W
Message Timeout (ms)
USHORT
R/W
Sleep Timeout (ms)
USHORT
R/W
Good Message Counter
USHORT
R/W
Bad Message Counter
USHORT
R/W
Exception Response Counter
Default
Value
276
0
0
0
0
0
7.4.1 Communication Settings
This register sets the communication parameters of the RS485 and RS232 ports. The default value is 276
(0x114) for RTU mode at 19200 baud, 8 bits, even parity, and 1 stop bit. The register is non-volatile.
15
Reserved
14
13
12
11
(default) RTU protocol
ASCII protocol
IP protocol
(default) 1 stop bit
2 stop bits
(default) Even parity
Odd parity
No parity
7 data bits
(default) 8 data bits
1200 baud
2400 baud
4800 baud
9600 baud
(default) 19200 baud
38400 baud
57600 baud
10
0
0
1
Register Bits
Protocol
Stop
9
8
7
0
1
1
0
0
0
0
1
Parity
6
5
0
0
1
Data
4
3
Baud Rate
2
1
0
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
0
1
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
When this register is written, the response will be returned at the previous communication settings. All
subsequent commands must be sent at the new settings. Attempting to write any combination of bits
not listed in the above table will result in an exception response with the ILLEGAL WRITE VALUE
exception code. Note that 7 data bits in the RTU transmission mode is an invalid combination; the
device will respond with an exception and the ILLEGAL WRITE VALUE exception code.
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PWS-600 User’s Manual
7.4.2 Message Timeout
If RTU or IP is selected, this register specifies the amount of idle time that must elapse before the device
recognizes the end of a message. A value of zero specifies a timeout that is selected automatically
based on the selected baud rate as described in the RTU Message Format section. If the master device
is unable to meet the default timing requirements, a fixed timeout from 5 to 50 milliseconds may be
specified. The register is non-volatile.
If ASCII mode is selected, this register specifies the maximum time that may elapse between characters
within a message when the ASCII transmission mode is selected. Intervals exceeding the timeout value
will cause the device to assume an error has occurred and discard the message. The valid range for the
timeout in ASCII mode is 1000 to 60000 milliseconds (1 to 60 seconds). The recommended setting for
most applications is 1000 milliseconds.
7.4.3 Sleep Timeout
This register specifies the amount of time allowed to elapse with no network activity before the device
enters its low power sleep mode. The valid range for the timeout is 0, or 1000 to 60000 milliseconds (1
to 60 seconds). A value of zero disables the low power sleep mode. The register is non-volatile.
After the device enters its sleep mode, any activity detected on the network will cause the device to
wake; however, the contents of the first message will most likely be missed. If this first message was a
command addressed to the device, the master device will receive no response and must retry the
command. Afterwards, as long as there is network activity more frequent than the sleep timeout
setting, the device will remain awake and process commands.
Note: The sleep timeout takes precedence over the message timeout. If the sleep timeout is
used (non-zero) it should be set greater than or equal to the message timeout.
7.4.4 Message Counters
The message counter registers provide diagnostic information for troubleshooting communication
problems. Each counter is reset by writing it to zero. The counters roll back to zero after the maximum
count value of 65535 is reached. The registers are volatile and will reset to zero if power is removed.
The Good Message Counter counts properly formatted messages that are addressed to the device. The
Bad Message Counter tracks the number of improperly formatted messages, such as those with a bad
CRC. The Exception Response Counter counts the number of messages received that were rejected with
an exception response.
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PWS-600 User’s Manual
7.5 Sensor Networks
The PWS-600 uses the concept of sensor networks to organize its sensor data logging features. Four
sensor networks are provided, numbered as shown below.
1 – RS485 Smart Sensor Network
2 – SDI-12 Smart Sensor Network
3 – Analog Sensor Network
4 – Discrete Sensor Network
Each sensor network has features common to all sensors on that network, and it is these features that
are discussed in this section. The data log configuration sensor command group registers specify how to
access and log sensors on a network.
7.5.1 RS485 Smart Sensor Network
RS485 sensor communication uses the signals on terminal block TB9, labeled “RS485 SENSORS”. The
terminal block provides terminals for power, ground, and the RS485 transceiver signals. 485B+ is the
positive transceiver signal and 485A- is the negative transceiver signal. The 485B+ signal is provided
with a 4.75K ohm resistor to the device’s internal +3.3 volt supply. The 485A- signal is provided with a
4.75K ohm termination resistor to GND. No signal termination resistor is provided internally. In most
low power applications, no additional termination resistor is necessary. If required, a resistor may be
added externally. The maximum offset of the signals from the GROUND at pin 1 is 7 volts. Both signals
are transient protected.
The RS485 sensor network can be configured to operate using one of three protocols: MODBUS RTU,
MODBUS ASCII, or SDI-12. A group of eight registers define and configure the network protocol. These
eight registers must be read and written within a single command. The format of these eight registers
varies based on the selected network protocol. The register block may not be written when logging is
enabled. Attempting to write the register block when logging is enabled will generate an exception
response with the READ-ONLY REGISTER exception code.
7.5.1.1 MODBUS RTU Sensor Network Configuration
The following table defines the RS485 sensor network configuration registers when configured to use
the MODBUS RTU protocol.
Register
1803
1804
1805
1806
1807
1808
Size
(Registers)
1
1
1
1
1
1
RS485 Sensor Network Configuration Group
Data
Type
Access
Name
USHORT
R/W
Communication Settings
USHORT
R/W
Message Timeout (ms)
USHORT
R/W
Network Wake Delay (ms)
USHORT
R/W
Retries (0 to 5)
USHORT
R/W
Sentinel Value
USHORT
R/W
Good Message Counter
29
Default
Value
0
0
1
0xFFFF
0
PWS-600 User’s Manual
1809
1810
1
1
USHORT
USHORT
R/W
R/W
Bad Message Counter
Exception Response Counter
0
0
7.5.1.2 Communication Settings
This register sets the protocol and the communication parameters for the network. Note that 7 data
bits in the RTU transmission mode is an invalid combination; the device will respond with an exception
and the ILLEGAL WRITE VALUE exception code.
15
0
14
0
13
0
Protocol
12
11
0
0
Register Bits
Stop
10
9
8
7
0
0
1
1 stop bit
0
2 stop bits
1
Even parity
Odd parity
No parity
7 data bits
8 data bits
1200 baud
2400 baud
4800 baud
9600 baud
19200 baud
38400 baud
57600 baud
Parity
6
5
0
0
1
Data
4
3
Baud Rate
2
1
0
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
0
1
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
For example, to configure the network for MODBUS RTU at 19200 baud, 8 data bits, even parity, and 1
stop bit, set this register to 276.
7.5.1.3 Message Timeout
The message timeout register specifies the amount of idle time that must elapse before the device
recognizes the end of an RTU message. The default value of zero signifies a timeout that is selected
automatically based on the selected baud rate as described in the RTU Message Format section. If any
slave device on the network is unable to meet the default timing requirements, a fixed timeout from 5
to 50 milliseconds may be specified. The default setting is zero.
7.5.1.4 Network Wake Delay
Some sensors may enter a low power mode if no network activity is detected for some period of time.
While in this mode, the sensor may not respond immediately to the first command it receives. To
accommodate sensors with this behavior, the device can be programmed to “wake” the sensor network
before starting requests for data.
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PWS-600 User’s Manual
If the Network Wake Delay is set to a non-zero value, the device will broadcast a Report Slave Id
command on the sensor network. This will generate network activity that will cause sensors to exit their
low power mode. Because this is a broadcast of a read command, sensors should not respond to the
command. The device will then delay the number of milliseconds specified by the Network Wake Delay
register before requesting data from the sensors. If the Network Wake Delay is set to zero, this
broadcast message is not sent.
7.5.1.5 Retries
This register specifies the number of times the device is to resend a command if a sensor does not
respond within the timeout specified for that command. Zero specifies no retries; only one command
attempt will be made. If the sensor fails to respond to a command after the allowed number of retries,
the sensor will be considered unresponsive and the sentinel value will be substituted for all registers
that were expected by the command.
7.5.1.6 Sentinel Value
The sentinel value is written in place of the data values for all registers that cannot be read by a
command. This will occur if a sensor fails to respond to a read register command, or if the sensor
returns an exception response.
7.5.1.7 Message Counters
The message counter registers provide diagnostic information for troubleshooting communication
problems. Each counter is reset by writing it to zero. The counters roll back to zero after the maximum
count value of 65535 is reached. The registers are volatile and will reset to zero if power is removed.
The Good Message Counter counts properly formatted messages that are returned to the device. The
Bad Message Counter tracks the number of improperly formatted messages, such as those with a bad
CRC. The Exception Response Counter counts the number of messages that were rejected with an
exception response.
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PWS-600 User’s Manual
7.5.1.8 MODBUS ASCII Sensor Network Configuration
The following table defines the RS485 sensor network configuration registers when configured to use
the MODBUS ASCII protocol.
Register
Offset
1803
1804
1805
1806
1807
1808
1809
1810
Size
(Registers)
1
1
1
1
1
1
1
1
RS485 Sensor Network Configuration Group
Data
Type
Access
Name
USHORT
R/W
Communication Settings
USHORT
R/W
Message Timeout (ms)
USHORT
R/W
Network Wake Delay (ms)
USHORT
R/W
Retries (0 to 5)
USHORT
R/W
Sentinel Value
USHORT
R/W
Good Message Counter
USHORT
R/W
Bad Message Counter
USHORT
R/W
Exception Response Counter
Default
Value
1000
0
1
0xFFFF
0
0
0
7.5.1.9 Communication Settings
This register sets the protocol and the communication parameters for the network.
15
0
14
0
13
0
Protocol
12
11
0
0
Register Bits
Stop
10
9
8
7
0
1
0
1 stop bit
0
2 stop bits
1
Even parity
Odd parity
No parity
7 data bits
8 data bits
1200 baud
2400 baud
4800 baud
9600 baud
19200 baud
38400 baud
57600 baud
Parity
6
5
0
0
1
Data
4
3
Baud Rate
2
1
0
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
0
1
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
For example, to configure the network for MODBUS ASCII at 19200 baud, 8 data bits, even parity, and 1
stop bit, set this register to 532.
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7.5.1.10 Message Timeout
The message timeout register specifies the maximum time that may elapse between characters within a
message. Intervals exceeding the timeout value will cause the device to assume an error has occurred
and discard the message. The valid range for the timeout is 1000 to 60000 milliseconds (1 to 60
seconds). The default setting is 1000 milliseconds.
7.5.1.11 Network Wake Delay
Some sensors may enter a low power mode if no network activity is detected for some period of time.
While in this mode, the sensor may not respond immediately to the first command it receives. To
accommodate sensors with this behavior, the device can be programmed to “wake” the sensor network
before starting requests for data.
If the Network Wake Delay is set to a non-zero value, the device will broadcast a Report Slave Id
command on the sensor network. This will generate network activity that will cause sensors to exit their
low power mode. Because this is a broadcast of a read command, sensors should not respond to the
command. The device will then delay the number of milliseconds specified by the Network Wake Delay
register before requesting data from the sensors. If the Network Wake Delay is set to zero, this
broadcast message is not sent.
7.5.1.12 Retries
This register specifies the number of times the device is to resend a command if a sensor does not
respond within the timeout specified for that command. Zero specifies no retries; only one command
attempt will be made. If the sensor fails to respond to a command after the allowed number of retries,
the sensor will be considered unresponsive and the sentinel value will be substituted for all registers
that were expected by the command.
7.5.1.13 Sentinel Value
The sentinel value is written in place of the data values for all registers that cannot be read by a
command. This will occur if a sensor fails to respond to a read register command, or if the sensor
returns an exception response.
7.5.1.14 Message Counters
The message counter registers provide diagnostic information for troubleshooting communication
problems. Each counter is reset by writing it to zero. The counters roll back to zero after the maximum
count value of 65535 is reached. The registers are volatile and will reset to zero if power is removed.
The Good Message Counter counts properly formatted messages that are returned to the device. The
Bad Message Counter tracks the number of improperly formatted messages, such as those with a bad
CRC. The Exception Response Counter counts the number of messages that were rejected with an
exception response.
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PWS-600 User’s Manual
7.5.1.15 SDI-12 over RS485 Sensor Network Configuration
The following table defines the RS485 sensor network configuration registers when configured to use
the SDI-12 protocol.
Register
Offset
1803
1804
1805
1806
1808
1809
1810
Size
(Registers)
1
1
1
2
1
1
1
RS485 Sensor Network Configuration Group
Data
Type
Access
Name
USHORT
R/W
Communication Settings
USHORT
R/W
Break Retries (0 to 5)
USHORT
R/W
Command Retries (0 to 5)
FLOAT
R/W
Sentinel Value
USHORT
R/W
Good Message Counter
USHORT
R/W
Bad Message Counter
USHORT
R/W
Retry Counter
Default
Value
2048
2
2
99999
0
0
0
7.5.1.16 Communication Settings
This register sets the protocol and communication parameters for the network.
15
0
14
0
13
0
Protocol
12
11
0
1
Register Bits
Stop
10
9
8
7
0
0
0
1 stop bit
0
Even parity
7 data bits
1200 baud
Parity
6
5
0
Data
4
3
Baud Rate
2
1
0
0
0
0
0
0
0
This register can only be written with a value of 2048 when the SDI-12 protocol is selected.
7.5.1.17 Retry Registers
These registers specify the number of times the device is to resend a break and command if an SDI-12
sensor does not respond within the required timeout. Zero specifies no retries; only one break and one
command attempt will be made. If the sensor fails to respond to a command after the allowed number
of retries, the sensor will be considered unresponsive and the SDI-12 sentinel value will be substituted
for all values that were expected by the command.
Each break attempt is followed by the specified number of command attempts. For example, if break
retries is set to 1 and command retries is set to 2:
1. The device will first send a break followed by the command.
2. If no response is received, the command will be retried two more times.
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PWS-600 User’s Manual
3. If still no response is received, the break will be retried, followed by three more attempts to
send the command.
4. If still no response is received, all values that we expected to be received will be logged with the
SDI-12 sentinel value.
7.5.1.18 Sentinel Value
The sentinel value is written in place of the measurement value for all sensor measurements that cannot
be read by a command. This will occur if an SDI-12 sensor fails to respond to a command, or if a
command is improperly structured to log more measurements than the sensor will return.
7.5.1.19 Message Counters
The message counter registers provide diagnostic information for troubleshooting communication
problems. Each counter is reset by writing it to zero. The counters roll back to zero after the maximum
count value of 65535 is reached. The registers are volatile and will reset to zero if power is removed.
The Good Message Counter counts properly formatted messages that are returned to the device. The
Bad Message Counter tracks the number of improperly formatted messages, such as those with a bad
CRC. The Exception Response Counter counts the number of messages that received no response.
7.5.2 SDI-12 Smart Sensor Network
The SDI-12 sensor network is a dedicated SDI-12 port that only supports the SDI-12 protocol. SDI-12
signals are available on terminal block TB8, labeled “SDI-12 SENSORS”. Three signals are used for power,
ground, and data. The data line is a bidirectional, tri-state signal using 5 volt logic that is capable of
driving up to 10 SDI-12 sensors. The maximum length of cable between the PWS-600 and any SDI-12
sensor is 200 feet (60 meters).
A group of eight registers define and configure the network. These eight registers must be read and
written within a single command. The register block may not be written when logging is enabled.
Attempting to write the register block when logging is enabled will generate an exception response with
the READ-ONLY REGISTER exception code.
Register
Offset
1813
1814
1815
1816
1818
1819
1820
Size
(Registers)
1
1
1
2
1
1
1
SDI-12 Sensor Network Configuration Group
Data
Type
Access
Name
USHORT
R/W
Communication Settings
USHORT
R/W
Break Retries (0 to 5)
USHORT
R/W
Command Retries (0 to 5)
FLOAT
R/W
Sentinel Value
USHORT
R/W
Good Message Counter
USHORT
R/W
Bad Message Counter
USHORT
R/W
Retry Counter
35
Default
Value
2048
2
2
99999
0
0
0
PWS-600 User’s Manual
7.5.2.1 Communication Settings
This register sets the protocol and communication parameters for the network. This register must be
written with a value of 2048.
15
0
14
0
13
0
Protocol
12
11
0
1
Register Bits
Stop
10
9
8
7
0
0
0
1 stop bit
0
Even parity
7 data bits
1200 baud
Parity
6
5
0
Data
4
3
Baud Rate
2
1
0
0
0
0
0
0
0
7.5.2.2 Retry Registers
These registers specify the number of times the device is to resend a break and command if an SDI-12
sensor does not respond within the required timeout. Zero specifies no retries; only one break and one
command attempt will be made. If the sensor fails to respond to a command after the allowed number
of retries, the sensor will be considered unresponsive and the SDI-12 sentinel value will be substituted
for all values that were expected by the command.
Each break attempt is followed by the specified number of command attempts. For example, if break
retries is set to 1 and command retries is set to 2:
1. The device will first send a break followed by the command.
2. If no response is received, the command will be retried two more times.
3. If still no response is received, the break will be retried, followed by three more attempts to
send the command.
4. If still no response is received, all values that we expected to be received will be logged with the
SDI-12 sentinel value.
7.5.2.3 Sentinel Value
The sentinel value is written in place of the measurement value for all sensor measurements that cannot
be read by a command. This will occur if an SDI-12 sensor fails to respond to a command, or if a
command is improperly structured to log more measurements than the sensor will return.
7.5.2.4 Message Counters
The message counter registers provide diagnostic information for troubleshooting communication
problems. Each counter is reset by writing it to zero. The counters roll back to zero after the maximum
count value of 65535 is reached. The registers are volatile and will reset to zero if power is removed.
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PWS-600 User’s Manual
7.5.3 Analog Sensor Network
A group of eight registers define and configure the network. These eight registers must be read and
written within a single command. The register block may not be written when logging is enabled.
Attempting to write the register block when logging is enabled will generate an exception response with
the READ-ONLY REGISTER exception code.
Register
Offset
1823
1824
1825
1826
1827
1828
1829
1830
Size
(Registers)
1
1
1
1
1
1
1
1
Analog Sensor Network Configuration Group
Data
Type
Access
Name
USHORT
R/W
Excitation Enable and Delay (ms)
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
Default
Value
0
0
0
0
0
0
0
0
7.5.3.1 Excitation Enable and Delay
Some analog sensors require an excitation signal to be applied in order to make a measurement. The
PWS-600 provides a voltage excitation (VEX) on terminal block TB2, and a resistive excitation (REX) on
terminal block TB1. In order to conserve power, these excitation outputs are normally turned off. This
register specifies how long to allow sensor outputs to stabilize after turning on excitation before taking
analog measurements. The delay is specified in milliseconds and can range from 0 to 65535
milliseconds. The amount of delay will have an impact on the fastest log interval that can be achieved.
Setting this register to zero disables excitation outputs (they will not be turned on during
measurements).
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PWS-600 User’s Manual
7.5.4 Discrete Sensor Network
The discrete sensor network requires no configuration at this time. A group of eight registers is reserved
to support future configuration options. These eight registers must be read and written within a single
command. The register block may not be written when logging is enabled. Attempting to write the
register block when logging is enabled will generate an exception response with the READ-ONLY
REGISTER exception code.
Register
Offset
1833
1834
1835
1836
1837
1838
1839
1840
Size
(Registers)
1
1
1
1
1
1
1
1
Discrete Sensor Network Configuration Group
Data
Type
Access
Name
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
USHORT
R/W
Reserved
38
Default
Value
0
0
0
0
0
0
0
0
PWS-600 User’s Manual
7.6 Data Log Configuration Registers
These registers set the polling and data log schedule. All data log configuration registers are nonvolatile.
Data Log Configuration Registers
Register
Number
1500
1501
1502
1506
1507
1508
1509
1517
1525
1533
1541
1549
1557
1565
1573
1581
1589
1597
1605
1613
1621
1629
1637
1645
1653
1661
1669
1677
Size
(Registers)
1
1
4
1
1
1
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
8
Data
Type
USHORT
USHORT
TIME
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
Access
R/W
R/W
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Name
Log Enable (0 = disabled, 1 = enabled)
Log Pause (seconds)
Next Scheduled Record
Log Interval (seconds)
Log Offset (seconds)
Number of Sensor Commands (0 to 32)
Sensor Command 1
Sensor Command 2
Sensor Command 3
Sensor Command 4
Sensor Command 5
Sensor Command 6
Sensor Command 7
Sensor Command 8
Sensor Command 9
Sensor Command 10
Sensor Command 11
Sensor Command 12
Sensor Command 13
Sensor Command 14
Sensor Command 15
Sensor Command 16
Sensor Command 17
Sensor Command 18
Sensor Command 19
Sensor Command 20
Sensor Command 21
Sensor Command 22
39
Default
Value
0
0
UTC
3600
0
0
PWS-600 User’s Manual
Data Log Configuration Registers
Register
Number
1685
1693
1701
1709
1717
1725
1733
1741
1749
1757
Size
(Registers)
8
8
8
8
8
8
8
8
8
8
Data
Type
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Name
Sensor Command 23
Sensor Command 24
Sensor Command 25
Sensor Command 26
Sensor Command 27
Sensor Command 28
Sensor Command 29
Sensor Command 30
Sensor Command 31
Sensor Command 32
Default
Value
7.6.1 Log Enable
This non-volatile register can be set to one of the following values. Attempting to write any other value
will result in an exception response with the ILLEGAL WRITE VALUE exception code.
0: Data log disabled. The next scheduled record registers will return zero. The data log
configuration can be edited.
1: Data log enabled. The next scheduled record registers will return the date and time of the
next scheduled log record per the defined schedule. Data log configuration registers are readonly and cannot be edited.
Attempting to write a log configuration register while the data log is enabled or paused will result in an
exception response with the READ-ONLY REGISTER exception code.
7.6.2 Log Pause
Use this register to pause the data log for a specified period of time, such as when pass-through access
to a sensor is necessary for calibration or maintenance. This register can only be written when the data
log is enabled. When the data log is disabled, this register will return zero.
Writing a value from 1 to 65535 will pause the data log for the specified number of seconds. While
paused, the next scheduled record registers will return zero, the data log configuration registers remain
read-only and cannot be edited, and pass-through communication is enabled. Data logging will resume
when the master device sets Log Pause back to zero, or will resume automatically when Log Pause
counts down to zero.
Attempting to write a log configuration register while the data log is enabled or paused will result in an
exception response with the READ-ONLY REGISTER exception code.
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PWS-600 User’s Manual
7.6.3 Next Scheduled Record
These registers return the date and time of the next scheduled record. These registers return zero if the
log is disabled or paused.
7.6.4 Log Interval
The log interval specifies the time between data records in seconds. The log interval can range from 0 to
43200 seconds (12 hours or 2 records per day) and must specify a whole number of records per day.
Setting the log interval to zero specifies an interval of 86400 seconds (24 hours or 1 record per day).
Attempting to write a value that would not result in a whole number of records per day will result in an
exception response with the ILLEGAL WRITE VALUE exception code.
Data records are synchronized with the real-time clock. The first data record each day is always
collected at 00:00:00 plus the log offset value. If, for example, the log interval is set to 21600 seconds (6
hours) and the log offset is zero, the PWS-600 will log 4 records per day at 00:00:00, 06:00:00, 12:00:00,
and 18:00:00.
7.6.5 Log Offset
The log offset specifies the offset of the first record from 00:00:00 each day. The offset is specified in
seconds and can range from 0 to one second less than the log interval. Attempting to write a value
outside this range will result in an exception response with the ILLEGAL WRITE VALUE exception code.
Note: If writing a new log interval would cause the log offset value to become invalid, the log
offset will be automatically reset to zero.
The log offset provides some flexibility in synchronizing daily data records with other system activities.
For example, if the log interval is set to 21600 seconds (6 hours) and the log offset is set to 7200 seconds
(2 hours), the PWS-600 will still collect 4 records per day, but the records will be offset to 02:00:00,
08:00:00, 14:00:00, and 20:00:00.
7.6.6 Number of Sensor Commands
This register specifies the number of sensor commands that will be used to read data from the sensors.
Up to 32 commands can be used to read up to 64 registers. Sensor commands are executed
sequentially beginning with sensor command 1. If zero is specified, no commands will be executed; only
local parameters (time, site id, device id, device serial number, device status, ambient temperature, and
input voltage) will be recorded.
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PWS-600 User’s Manual
7.6.7 Sensor Command Groups
Each sensor command (1 to 32) consists of a group of 8 registers. Each register in the following table is
an offset from the first register of the sensor command group as specified in the Data Log Configuration
Registers Table.
Sensor Command Group
Register
Offset
0
1–7
Size
(Registers)
1
7
Data
Type
USHORT
---
Access
R/W
R/W
Name
Sensor Network (1-4)
(sensor network protocol dependent)
Default
Value
---
All 8 registers in a group must be read and written within a single command. The first register in each
command group specifies the sensor network on which the sensor is located. The RS485 smart sensor
network is sensor network 1, the SDI-12 smart sensor network is sensor network 2, the analog sensor
network is network 3, and the discrete network is network 4. The function of the remaining registers in
each command group varies depending on the configuration of the selected network.
Note: changing the sensor network selection may cause other settings in the command group to
become invalid due to a change in the network protocol. Configure sensor networks before
selecting a sensor network.
7.6.8 MODBUS Command Group Format
The following table defines the sensor command group for a smart sensor network configured to use a
MODBUS protocol (RTU or ASCII). Each register in the table is an offset from the first register of the
sensor command group as specified in the Data Log Configuration Registers Table.
Sensor Command Group
Register
Offset
0
1
2
3
4
5
6
7
Size
(Registers)
1
1
1
1
1
1
1
1
Data
Type
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
USHORT
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Name
Sensor Network (network 1 only)
Sensor Address (1 to 247)
Data Type (1 to 4)
Start Register Number (1 to 65535)
Number of Registers (1 to 64)
Response Timeout (milliseconds)
Reserved
Reserved
Default
Value
1
1
3
1
1
1000
0
0
Each sensor command generates a MODBUS read command for the specified data type. The data read
from the sensor are added to the current data record. If several non-sequential registers or data types
need to be read from a sensor, multiple read register commands can be sent to the same sensor.
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PWS-600 User’s Manual
7.6.8.1 MODBUS Sensor Address
This register specifies the sensor’s network address.
7.6.8.2 MODBUS Data Type
This register specifies the data type to be read from the sensor according to the following table.
MODBUS Sensor Command Data Types
Register
Value
1
2
3
4
MODBUS Data Type
Coils
Discrete Inputs
Holding Registers
Input Registers
The default value is 3, to read holding registers. Attempting to write a value not in the table will result
in an exception response with the ILLEGAL WRITE VALUE exception code.
7.6.8.3 MODBUS Start Register Number
For coils (1) and discrete input (2) data types, this register specifies the first coil or discrete input to read.
For holding register (3) and input register (4) data types, this register specifies the first register number
to read.
7.6.8.4 MODBUS Number of Registers
For coils (1) and discrete input (2) data types, this register specifies the number of coils or discrete
inputs to read. Each coil or discrete input is represented as a single bit and is packed 16 bits per register
in the data record, beginning at the least significant bit of each register.
For holding register (3) and input register (4) data types, this register specifies the number of registers to
read. Each register read is added sequentially to the data record.
A maximum of 64 registers can be specified across all read register commands. If the sensor returns an
exception to the Read Registers command, the sentinel value will be recorded for each requested
register.
7.6.8.5 MODBUS Response Timeout
The response timeout specifies the maximum amount of time the device should allow for the sensor to
make a measurement and respond to the command. If a response is not received within the specified
timeout, the device will retry the command if specified. If no response is received after the specified
number of retries, the sentinel value will be recorded for each requested register.
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PWS-600 User’s Manual
7.6.9 SDI-12 Command Group Format
The following table defines the sensor command group for a smart sensor network configured to use
the SDI-12 protocol. Each register in the table is an offset from the first register of the sensor command
group as specified in the Data Log Configuration Registers Table.
SDI-12 Sensor Command Group
Register
Offset
0
1
2
3
5
6
7
Size
(Registers)
1
1
1
2
1
1
1
Data
Type
USHORT
USHORT
USHORT
ULONG
USHORT
USHORT
USHORT
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Name
Sensor Network (1 or 2 in SDI-12 mode)
Sensor Address
Measurement Command
Measurement Selection Bit Mask
Reserved
Reserved
Reserved
Default
Value
1
48
0
1
0
0
0
Each sensor command generates the specified measurement command, reads the sensor response,
then adds a FLOAT type value to the current data record for each selected measurement.
7.6.9.1 SDI-12 Sensor Address
This register specifies the sensor’s network address. SDI-12 addresses are ranges of ASCII characters as
defined in the following table. Address “0” is the default sensor address initially set by the
manufacturer as defined by the SDI-12 specification. All sensors are required to support the address
range “0” to “9”. The other address ranges are optional and might not be supported by all sensors.
ASCII
“0”
“1” to “9”
“A” to “Z”
“a” to “z”
Decimal
48
49 to 57
65 to 90
97 to 122
SDI-12 Sensor Address Ranges
Hexadecimal
0x30
0x31 to 0x39
0x41 to 0x5A
0x61 to 0x7A
Description
Default
Standard Support
Optional Support
Optional Support
Attempting to write any other value will result in an exception response with the ILLEGAL WRITE VALUE
exception code.
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PWS-600 User’s Manual
7.6.9.2 SDI-12 Measurement Command
This register specifies the measurement command to be sent to the sensor. The device supports all of
the standard SDI-12 measurement commands as outlined in the following table.
Register Value
0
1 to 9
10
11 to 19
20
21 to 29
30
31 to 39
40 to 49
50 to 59
SDI-12 Measurement Command Table
SDI-12 Command
Description
“M”
Start measurement
“M1” to “M9”
Start additional measurement
“MC”
Start measurement with CRC
“MC1” to “MC9”
Start additional measurement with CRC
“C”
Start concurrent measurement
“C1” to “C9”
Start concurrent additional measurement
“CC”
Start concurrent measurement with CRC
“CC1” to “CC9”
Start concurrent additional measurement with CRC
“R0” to “R9”
Read continuous measurement
“RC0” to “RC9”
Read continuous measurement with CRC
Attempting to write any other value will result in an exception response with the ILLEGAL WRITE VALUE
exception code.
7.6.9.3 SDI-12 Measurement Selection Bit Mask
This 32-bit register specifies which measurements returned by the sensor are to be logged. Bit 0
corresponds to the first measurement returned. Bit 31 corresponds to the 32nd measurement returned.
Any bit set to a one selects the corresponding measurement to be logged. Any bit set to a zero will
cause the corresponding measurement to be discarded.
Note: Version 1.3 of the SDI-12 specification limits the number of measurements returned by a
sensor in response to a given measurement command to a maximum of 20. Future versions of
the specification may increase this limit. The PWS-600 will support up to 32 measurement values
from a sensor, allowing for some future expansion.
For example, a sensor returns three parameters A, B, and C, to measurement command “M” and the
measurement selection bit mask is set to 5 (binary 00000000 00000101). Measurements A and C will be
logged, and measurement B will be discarded.
If a sensor does not return enough measurements to match a set bit, the SDI-12 sentinel value will be
recorded in place of the measurement. For example, if a sensor returns three parameters to a
measurement command A, B, and C, and the measurement selection bit mask is set to 13 (binary
00000000 00001101), measurements A and C will be logged, measurement B will be discarded, and the
SDI-12 sentinel value will be logged in place of the missing 4th measurement.
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PWS-600 User’s Manual
7.6.10 Analog Command Group Format
The following table defines the sensor command group for an analog sensor network. Each register in
the table is an offset from the first register of the sensor command group as specified in the Data Log
Configuration Registers Table.
Analog Sensor Command Group
Register
Offset
0
1
2
3
4
6
Size
(Registers)
1
1
1
1
2
2
Data
Type
USHORT
USHORT
USHORT
USHORT
FLOAT
FLOAT
Access
R/W
R/W
R/W
R/W
R/W
R/W
Name
Sensor Network (network 3 only)
Analog Channel (1 to 49)
Measurements to Average (1 to 25)
Output Format
Scale Factor (measurement units/mV)
Offset (measurement units)
Default
Value
3
0
1.0
0.0
7.6.10.1 Analog Channel
This register specifies the analog channel to be measured. An analog channel defines the physical
analog inputs to be used for the measurement, as well as preconfigured ranges and functions.
Channel
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
+Input
ANI1
AIN2
AIN3
AIN4
AIN5
AIN6
ANI1
AIN2
AIN3
AIN4
AIN5
AIN6
ANI1
AIN2
AIN3
AIN4
AIN5
AIN6
-Input
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
AGND
Range
0 to 5000 mV
0 to 5000 mV
0 to 5000 mV
0 to 5000 mV
0 to 5000 mV
0 to 5000 mV
0 to 2000 mV
0 to 2000 mV
0 to 2000 mV
0 to 2000 mV
0 to 2000 mV
0 to 2000 mV
0 to 1000 mV
0 to 1000 mV
0 to 1000 mV
0 to 1000 mV
0 to 1000 mV
0 to 1000 mV
Description
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
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PWS-600 User’s Manual
Channel
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
+Input
ANI1
AIN2
AIN3
AIN4
AIN5
AIN6
AIN2
AIN4
AIN6
AIN2
AIN4
AIN6
AIN2
AIN4
AIN6
AIN2
AIN4
AIN6
AIN2
AIN4
AIN6
AIN2
AIN4
AIN6
AIN2
AIN4
AIN6
AIN5
-Input
AGND
AGND
AGND
AGND
AGND
AGND
AIN1
AIN3
AIN5
AIN1
AIN3
AIN5
AIN1
AIN3
AIN5
AIN1
AIN3
AIN5
AIN1
AIN3
AIN5
AIN1
AIN3
AIN5
AIN1
AIN3
AIN5
AGND
Range
0 to 500 mV
0 to 500 mV
0 to 500 mV
0 to 500 mV
0 to 500 mV
0 to 500 mV
±2000 mV
±2000 mV
±2000 mV
±1000 mV
±1000 mV
±1000 mV
±500 mV
±500 mV
±500 mV
±250 mV
±250 mV
±250 mV
±125 mV
±125 mV
±125 mV
±60 mV
±60 mV
±60 mV
±30 mV
±30 mV
±30 mV
0 to 20.5 mA
47
AIN6
AGND
0 to 20.5 mA
48
AIN4
AGND
-50 to 200 °C
49
AIN4
AIN3
-50 to 200 °C
Description
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Single-ended, consider BAT+ or SWBATx for power
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Differential, consider VEX & AGND for excitation
Current loop, jumper AIN5 to LOOP1,
consider BAT+ or SWBATx for power
Current loop, jumper AIN6 to LOOP2,
consider BAT+ or SWBATx for power
2-wire Pt1000 Platinum RTD, jumper AIN4 to REX
One wire to AIN4, one wire to AGND
4-wire Pt1000 Platinum RTD, jumper AIN5 to REX
Power pair to AIN5 and AGND
Sense pair to AIN4 and AIN3
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PWS-600 User’s Manual
7.6.10.2 Measurements to Average
This register specifies the number of consecutive channel measurements to average. The number of
readings averaged will have an impact on the fastest log interval that can be achieved. Setting this
register to one disables averaging.
7.6.10.3 Output Format
The output format specifies how the sensor measurement is formatted and added to the current data
record.
Value
0
1
2
Output Format
Description
USHORT (1 register)
SHORT (1 register)
FLOAT (2 registers)
The internal measurement result is a floating point value; specifying a FLOAT output places the
measurement result directly into the current data record as a FLOAT.
If an USHORT value is specified, the floating point value is rounded to an unsigned integer value in the
range 0 to 65535. If the rounded value is greater than 65535, 65535 is output. If the rounded value is
less than zero, then zero is output.
If a SHORT value is specified, the floating point value is rounded to a signed integer value in the range
-32768 to +32767. If the rounded value is greater than +32767, +32767 is output. If the rounded value
is less than -32768, -32768 is output.
7.6.10.4 Scale Factor and Offset
The scale factor and offset can be used to convert the measured value to the appropriate sensor
parameter units according to the following equation:
Measured Output = Scale Factor (Measured Value) + Offset
The scale factor and offset are applied before conversion to one of the short formats occurs. Note also
that the platinum RTD channels provide temperature in Celsius units. Scaling is only necessary to
convert units or improve the resolution when using one of the integer formats.
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PWS-600 User’s Manual
7.6.11 Discrete Command Group Format
The following table defines the sensor command group for a discrete sensor network. Each register in
the table is an offset from the first register of the sensor command group as specified in the Data Log
Configuration Registers Table.
Discrete Sensor Command Group
Register
Offset
0
1
2
3
4
6
Size
(Registers)
1
1
1
1
2
2
Data
Type
USHORT
USHORT
USHORT
USHORT
FLOAT
FLOAT
Access
R/W
R/W
R/W
R/W
R/W
R/W
Name
Sensor Network
Discrete Channel
Reserved
Output Format
Scale Factor (measurement units/mV)
Offset (measurement units)
Default
Value
0
0
1.0
0.0
7.6.11.1 Discrete Channel
This register specifies the discrete channel to be measured. A discrete channel defines the physical
discrete inputs to be used for the measurement, as well as preconfigured ranges and functions.
Channel
1
2
3
Input
DIO1
DIO2
DIO1
4
DIO2
5
DIO1
6
DIO2
7
DIO1
8
DIO2
9
10
DIO1
DIO2
Description
Input state (0 or 1)
Input state (0 or 1)
Positive edge debounced switch counter, counts up to 65535 switch closures
between log records, resets back to zero after record is logged
Positive edge debounced switch counter, counts up to 65535 switch closures
between log records, resets back to zero after record is logged
Negative edge debounced switch counter, counts up to 65535 switch closures
between log records, resets back to zero after record is logged
Negative edge debounced switch counter, counts up to 65535 switch closures
between log records, resets back to zero after record is logged
Pulse counter, counts up to 65535 pulses between log records, resets back to
zero after record is logged
Pulse counter, counts up to 65535 pulses between log records, resets back to
zero after record is logged
Frequency counter, 1 second gate measures from 1 to 65535 Hz.
Frequency counter, 1 second gate measures from 1 to 65535 Hz.
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PWS-600 User’s Manual
7.6.11.2 Output Format
The output format specifies how the sensor measurement is formatted and added to the current data
record.
Value
0
1
2
Output Format
Description
USHORT (1 register)
SHORT (1 register)
FLOAT (2 registers)
The internal measurement result is a floating point value; specifying a FLOAT output places the
measurement result directly into the current data record as a FLOAT.
If an USHORT value is specified, the floating point value is rounded to an unsigned integer value in the
range 0 to 65535. If the rounded value is greater than 65535, 65535 is output. If the rounded value is
less than zero, then zero is output.
If a SHORT value is specified, the floating point value is rounded to a signed integer value in the range
-32768 to +32767. If the rounded value is greater than +32767, +32767 is output. If the rounded value
is less than -32768, -32768 is output.
7.6.11.3 Scale Factor and Offset
The scale factor and offset can be used to convert the measured value to the appropriate sensor
parameter units according to the following equation:
Measured Output = Scale Factor (Measured Value) + Offset
The scale factor and offset are applied before conversion to one of the short formats occurs.
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PWS-600 User’s Manual
7.6.12 Last Sensor Readings
These registers allow a master device to read the last sensor readings. The last sensor readings may be
generated by the last log record, or by the read sensors device command. The format of the data
registers is determined by the sensor command groups. These registers are not encrypted. The
registers are volatile and will reset to zero if power is removed.
Last Data Log Record Registers
Register
Number
2300
2304
2305
2306
2308
2309
2310
2311
2312
Size
(Registers)
4
1
1
2
1
1
1
1
64
Data
Type
TIME
USHORT
USHORT
ULONG
USHORT
SHORT
USHORT
USHORT
USHORT
Access
R
R
R
R
R
R
R
R
R
Name
Date and Time
Site Id
Device Id
Device Serial Number
Device Status
Ambient Temperature
Input Voltage
Register Count
Data Registers
51
Default
Value
°C x 10
mV
PWS-600 User’s Manual
7.7 Switched Power Outputs
The PWS-600 provides two switched battery outputs labeled SWBAT1 and SWBAT2. Each output is
capable of switching up to 0.5 amperes and can be programmed to turn on during the measurement
time to power sensors, or programmed to turn on and off on a daily schedule to power a radio or
cellular modem for remote access.
A third switched power output is available on the RS232 connector on pin 9. This +5V, 275 mA supply
can be used to power master-side RS232 communication accessories such as a modem or Ethernet
adapter.
Switched Power Output Registers
Register
Number
2401
2402
2413
2424
Size
(Registers)
1
11
11
11
Data
Type
USHORT
USHORT
USHORT
USHORT
Access
R
R/W
R/W
R/W
Name
Switched Output Status
Switched Output SWBAT1 Configuration
Switched Output SWBAT2 Configuration
RS232 +5V Switched Output Configuration
Default
Value
0
7.7.1 Switched Output Status
This read-only register provides the status of each of the switched outputs.
15
14
reserved
13
12
reserved
Switched Output Status Register
11
10
9
8
7
6
5
4
reserved
reserved
reserved RS232 +5V
3
2
SWBAT2
1
0
SWBAT1
Each switched output is described by a pair of bits, indicating its current output state. The status of
unsupported (reserved) switched outputs will always be indicated as off.
Bits
00
01
10
11
Switched Output States
Description
Off
Fault (output shorted or overloaded)
Marginal (output < 90% of expected)
On
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PWS-600 User’s Manual
7.7.2 Switched Power Output Configuration
The following table defines the switched power output configuration group. Each register in the table is
an offset from the first register in the group as specified in the Switched Power Output Registers Table.
Registers in this group may be accessed individually or as a group.
Register
Offset
0
1
2
Size
(Registers)
1
1
9
Switched Power Output Configuration Group
Data
Type
Access
Name
USHORT
R/W
Switched Output Mode
USHORT
R/W
Measurement Warm-up Delay (ms)
USHORT
R/W
Switched Output Schedule
Default
Value
0
0
0
7.7.2.1 Switched Output Modes
The output mode specifies how the switched power output will be controlled.
Value
0
1
2
3
Output Mode
Description
Always Off
On to Measure
On by Schedule
Always On
When “On to Measure” is selected, the device will turn on the switched power output prior to taking a
sensor measurement of any kind, wait the specified measurement delay, and then take the
measurements specified by the log commands. This mode is used to control power to sensors that draw
too much current to be left on continuously.
When “On by Schedule” is selected, the device will turn the switched power output on and off as
specified by the schedule register bits, independent of the log schedule. In this mode, the measurement
warm-up delay is not used. This mode may be used to control external interface equipment, such as a
cellular modem, that may draw too much power to be left on continuously.
“On Always” turns the output on continuously. Combined with the “Off” mode, this mode permits
remote control or test of a switched power output.
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PWS-600 User’s Manual
7.7.2.2 Switched Output Schedule
These nine registers comprise 144 bits, each representing a 10 minute interval of the day. Bit 0 of the
first register (offset 2) represents 00:00:00 to 00:09:59. Bit 15 of the last register (offset 10) represents
23:50:00 to 23:59:59. For each bit that is set, the output will be turned on during the corresponding 10
minute interval each day. The following table illustrates the bit mapping of the schedule registers.
Register
Offset
2
3
4
5
6
7
8
9
10
Switched Output Schedule Register Bit Start Times (UTC)
Bit 15
Bit 12
Bit 9
Bit 6
Bit 3
Bit 0
02:30
05:10
07:50
10:30
13:10
15:50
18:30
21:10
23:50
00:00
02:40
05:20
08:00
10:40
13:20
16:00
18:40
21:20
02:00
04:40
07:20
10:00
12:40
15:20
18:00
20:40
23:20
01:30
04:10
06:50
09:30
12:10
14:50
17:30
20:10
22:50
01:00
03:40
06:20
09:00
11:40
14:20
17:00
19:40
22:20
00:30
03:10
05:50
08:30
11:10
13:50
16:30
19:10
21:50
As an example, it is desired to have a cellular modem on from 12:00 to 1:00 P.M. (12:00 to 13:00) each
day, Mountain Standard Time (MST). Since MST is UTC – 6 hours, that corresponds to 18:00 to 19:00
UTC. Set bits 12 through 15 of register offset 8 (61440 or 0xF000) and bits 0 through 1 of register offset
9 (3 or 0x0003).
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PWS-600 User’s Manual
7.8 Discrete Outputs
The two discrete I/O terminals on the PWS-600 can be used as inputs or outputs. This section describes
how to program the discrete I/O as outputs. When programmed as an output, the discrete cannot be
used as an input.
Discrete Output Registers
Register
Number
2501
2502
2508
Size
(Registers)
1
6
6
Data
Type
USHORT
USHORT
USHORT
Access
R
R/W
R/W
Default
Value
0
Name
Discrete Output Status
Discrete Output 1 Configuration
Discrete Output 2 Configuration
7.8.1 Discrete Output Status
This read-only register provides the status of each of the discrete outputs. Each discrete output is
described by a single bit, indicating its current output state (0 = off, 1 = on). The status of unsupported
outputs will always be indicated as off.
15
0
14
0
13
0
12
0
11
0
10
0
Discrete Output Status Register
9
8
7
6
5
0
0
0
0
0
4
0
3
0
2
0
1
0
DIO2 DIO1
7.8.2 Discrete Output Configuration
The following table defines the discrete output configuration group. Each register in the table is an
offset from the first register in the group as specified in the Discrete Output Registers Table. Registers in
this group may be accessed individually or as a group.
Discrete Output Configuration Group
Register
Offset
0
1
2
3
5
Size
(Registers)
1
1
1
2
1
Data
Type
USHORT
USHORT
USHORT
FLOAT
USHORT
Access
R/W
R/W
R/W
R/W
R/W
Name
Discrete Output Mode
Data Record Offset (0 to 63)
Data Record Data Type
Alarm Threshold
Hysteresis (0 to 10% in 0.1% increments)
55
Default
Value
0
0
0
0
0
PWS-600 User’s Manual
7.8.2.1 Discrete Output Modes
The output mode specifies how the discrete output will be controlled.
Value
0
1
2
3
Output Mode
Description
Always Off
High Alarm
Low Alarm
Always On
When “High Alarm” is selected, the device will turn on the discrete output if the assigned logged value is
greater than or equal to the programmed alarm threshold. The output will be turned off when the
assigned logged value returns below the alarm threshold minus the hysteresis setting.
When “Low Alarm” is selected, the device will turn on the discrete output if the assigned logged value is
less than or equal to the programmed alarm threshold. The output will be turned off when the assigned
logged value returns above the alarm threshold plus the hysteresis setting.
“On Always” turns the output on continuously. Combined with the “Off” mode, this mode permits
remote control or test of a discrete output.
7.8.2.2 Data Record Offset
This register specifies the offset into the last logged record where the logged value resides. The offset
must be aligned with a valid log value in order for the alarm value comparison to be valid.
7.8.2.3 Data Record Data Type
This register specifies the data type of the logged value pointed to by the data record offset. The data
type must match the type of the recorded value in order for the alarm value comparison to be valid.
The logged value will be converted to a floating point value for comparison to the alarm threshold.
Value
0
1
2
Data Types
Description
USHORT (1 register)
SHORT (1 register)
FLOAT (2 registers)
7.8.2.4 Alarm Threshold
This register specifies the alarm threshold. It must be of the same units and scaling as the recorded log
value.
7.8.2.5 Hysteresis
Hysteresis can range from 0.0 to 10.0% of the alarm threshold and is specified in 0.1% increments. For
example, 2.5% is written as 25. Adding hysteresis prevents chatter of the discrete output if the logged
value is moving slowly about the alarm threshold.
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PWS-600 User’s Manual
7.9 Data Log Recording Registers
These registers configure data log security and allow the MODBUS master device to record additional
information in the data log such as user notes.
Data Log Recording Registers
Register
Number
1300
1320
1321
Size
(Registers)
8
1
64
Data
Type
STRING
USHORT
USHORT
Access
W
W
W
Name
Default
Value
Encryption Key
Register Count
Data Registers
7.9.1 Encryption Key
Write this 8-register string to set a 128-bit encryption key. Afterwards, all data records written to the
data log will be encrypted using this key. The registers are write-only so that the key is protected. The
registers are non-volatile, so the key need only be written once prior to recording data. When shipped
from the factory or after a factory defaults command is issued, the key is erased and encryption is
disabled. Issuing a factory defaults command does not remove encryption from data already stored in
the data log.
It is recommended that the user not mix data recorded with different encryption keys, or mix encrypted
and unencrypted data in the same log, as this will make decrypting the log difficult. Changing the
encryption key does not change the encryption of previously recorded data. The data log should be
erased prior to, or immediately after, changing the encryption key.
Note: It is the responsibility of the user to manage encryption keys. Once written, the
encryption key cannot be read out of the device. Once data is recorded with encryption, it
cannot be decrypted without the original key.
7.9.2 Recording Data
Data is recorded in the data log using the following procedure.
1.
Write the number of registers to be recorded (1 to 64) to register 1320. Attempting to write a
value outside this range will result in an exception response with the ILLEGAL WRITE VALUE
exception code.
2. Write data registers beginning at register 1321. Only the number of data registers specified by
the register count can be written. Attempting to write more data registers than specified by the
register count will result in an exception response with the ILLEGAL ADDRESS VALUE exception
code. A single Write Multiple Registers function can be used to write the register count and the
data registers in one transaction.
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PWS-600 User’s Manual
3. When the last data register is written as determined by the register count, the device will write
the record to the data log along with the time, site id, device id, device serial number, device
status, ambient temperature, and input voltage. The typical response time to this write is less
than 100 milliseconds. The maximum response time is 3 seconds.
The register count and data registers are write-only to protect unencrypted data from being read.
One of the primary purposes of allowing the MODBUS master device to write data asynchronously to
the logged sensor data is to be able to insert notes. Notes can be in any suitable format (ASCII, packed
ASCII, Unicode, etc.); however, for easy decoding of the log data, the record size (register count) of the
notes should be something different than the record size of the sensor data records. Assigning note
records to a constant size of 64 registers is recommended. If the defined STRING data type is used, this
allows notes to be up to 128 characters long.
7.9.3 Recording Speed
The PWS-600 is capable of recording data as fast as 1 record per second provided that the data log has
not wrapped around. Once the data log has wrapped around, the recording rate drops to 1 record every
5 seconds. This is necessary in order to provide time for block erasures when the oldest data is erased.
In addition, the log configuration settings must be considered. The response timeout value and the
number of retries will affect the maximum recording speed.
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PWS-600 User’s Manual
7.10 Data Log Retrieval Registers
These registers allow a master device to retrieve data records from the data log.
Data Log Retrieval Registers
Register
Number
1400
1402
1404
1406
1408
1409
1411
1412
1416
1417
1418
1420
1421
1422
1423
1424
1488
Size
(Registers)
2
2
2
2
1
2
1
4
1
1
2
1
1
1
1
64
4
Data
Type
ULONG
ULONG
ULONG
ULONG
USHORT
ULONG
USHORT
TIME
USHORT
USHORT
ULONG
USHORT
SHORT
USHORT
USHORT
USHORT
USHORT
Access
R
R
R
R
R/W
R/W
R
R
R
R
R
R
R
R
R
R
R
Name
Data Log Size (bytes)
Data Log Used (bytes)
Lowest Record Number
Highest Record Number
Download Record Count
Record Number
Record Size in Registers
Date and Time
Site Id
Device Id
Device Serial Number
Device Status
Ambient Temperature
Input Voltage
Register Count
Data Registers
Encryption Padding Registers
Default
Value
4,194,304
0
0
0
0
0
0
0
0
0
0
0
°C x 10
mV
0
0
7.10.1 Data Log Size
This register returns the data log memory size in bytes.
7.10.2 Data Log Used
This register returns the number of data log memory bytes currently used. Combined with the data log
size, the register can be used to calculate the percent of memory used and percent of memory
remaining.
7.10.3 Lowest and Highest Record Numbers
If no records have been logged, both the lowest and highest record numbers will be zero. Records are
numbered beginning at record one. The highest record number will increment with each record logged
(the highest record number is also the total number of records recorded since the log was last erased).
As long as the data log hasn’t wrapped, the lowest record number will remain at one. Once the log
wraps around, the lowest record number will begin to advance as the oldest data is deleted. Every
record will have a unique and always increasing number. If the user keeps track of the last record
number that was retrieved, only higher record numbers will need to be retrieved at the next download.
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PWS-600 User’s Manual
7.10.4 Download Record Count
This register specifies the maximum number of records to transfer when the Data Log Download
command is used. The default value of zero permits continuous streaming of data records. This record
is non-volatile. The content of this register has no effect when reading data records via the Data Log
Retrieval registers.
7.10.5 Record Number
Write this register to specify the data record number to read. If the write is successful, the remaining
registers are filled in with the record data and are ready to be read. The average response time is 500
milliseconds seconds. The maximum response time is 1000 milliseconds.
Attempting to write a record number less than the lowest record number or greater than the highest
record number will result in an exception response with the ILLEGAL WRITE VALUE exception code.
If a data record is found to be corrupt the device will return an exception response with the CORRUPT
DATA RECORD exception code. As much of the data record will be retrieved as possible; however, the
register count and/or contents of the record are suspect. If the register count returns zero, the record
could not be retrieved. A corrupt record can occur if power fails during the time the data record is being
written.
7.10.6 Record Size
After writing the record number, this register provides the size of the record in registers. The size
includes all registers from the first register of the time stamp to the last data register.
7.10.7 Record Data
After writing the record number, the record data registers can be read. All data registers may be read,
including those beyond the record size. This permits the master device to read all of the data record
registers with one command regardless of the record size. Only the data registers specified by the
register count will contain valid information.
If the data is unencrypted, the register numbers and sizes shown in the table above can be read to
extract portions of the data record if not all of the information is needed.
If the data is encrypted, reading individual registers from the table will not be useful. A read registers
command must be used to read the number of registers specified by the record size. All of the registers
in the record are required in the decryption process.
The unencrypted record format for logged data is the same as that described for the data polling
registers.
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PWS-600 User’s Manual
7.10.8 Data Decryption
The Prairie View Software that comes with the device provides data decryption and the capability to
view and export data from encrypted logs.
The Advanced Encryption Standard is supported by many operating systems, so it is possible for user
applications and third-party software to decrypt logs, providing that the original encryption key is
known.
7.10.9 Data Retrieval Procedure
The following procedure describes data retrieval using conventional MODBUS register read and write
commands.
1. The master device reads the lowest and highest record number registers to determine the valid
record number range and selects the range of records to be downloaded.
2. The master device writes a record number to the record number register. The PWS-600
retrieves the record from the data log.
3. The master device reads the record size register to determine the number of registers in the
record.
4. The master device reads the number of registers specified by the size registers beginning with
the time register.
5. Optionally, after the master device has written the record number, it can simply read all record
registers from the register size through the encryption padding registers and decode the record
later.
6. The master device repeats steps 2 through 6 until all selected records have been retrieved.
7.10.10
Data Log Download Command
The following procedure describes the use of the data log download command. This command provides
considerably faster downloads as compared to conventional register access.
1. The master device reads the lowest and highest record number registers to determine the valid
record number range.
2. The master device writes the first record number to be downloaded to the record number
register. To download all data, set the record number register equal to the lowest record
number. The PWS-600 has a maximum response time of 1000 milliseconds to this command.
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PWS-600 User’s Manual
3. The master device writes the data log download command to the command register. The PWS600 will return a standard response to this write register command with a maximum response
time of 1000 milliseconds.
4. After a 500 millisecond delay, the PWS-600 will begin to stream the number of records specified
by the download record count, beginning at the record specified by the record number register.
If the download record count is set to zero, the download will continue uninterrupted to the
highest record number. Each record is constructed as a standard MODBUS read registers
response that begins at the record number register and contains all registers in the record.
There will be little or no delay between records.
5. After all records have been sent, the PWS-600 will send an exception response with the END
DOWNLOAD exception code.
6. The master device must be capable of receiving records back-to-back until it detects the END
DOWNLOAD exception.
The user should consider the following when using this command to download data.

There is no handshaking. The master device must be capable of receiving records back-to-back
with little or no delay between records. Since the record number is included in each record sent
and each record contains a CRC or LRC, the master device can determine if any records were
missed.

On the RS485 port, there is no way to cancel the command. The PWS-600 will stream data until
it is done. The network is unavailable for any other communication until the download is
finished.

If the PWS-600 encounters a corrupt record during the download, it will send an exception
response with the CORRUPT DATA RECORD exception code in place of the corrupt record and
the download will continue.
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7.10.11
Last Data Log Record
These registers allow a master device to read the last data record from the data log directly. The format
and encryption requirements are the same as those for a retrieved record.
Last Data Log Record Registers
Register
Number
2200
2202
2203
2207
2208
2209
2211
2212
2213
2214
2215
2279
Size
(Registers)
2
1
4
1
1
2
1
1
1
1
64
4
Data
Type
ULONG
USHORT
TIME
USHORT
USHORT
ULONG
USHORT
SHORT
USHORT
USHORT
USHORT
USHORT
Access
R/W
R
R
R
R
R
R
R
R
R
R
R
Name
Record Number
Record Size in Registers
Date and Time
Site Id
Device Id
Device Serial Number
Device Status
Ambient Temperature
Input Voltage
Register Count
Data Registers
Encryption Padding Registers
Default
Value
°C x 10
mV
The last data log record is only valid while data logging is enabled. If the data log is disabled, or if no
data record has been recorded since the data log was enabled, the record number will return zero to
indicate that the remaining record data is not valid.
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7.11 Sensor Network Pass-Through Registers
The PWS-600 supports pass-through from its communication port network to a sensor network to assist
in the configuration and maintenance of connected sensors.
Register
Number
2000
2001
Size
(Registers)
1
64
Sensor Network Pass-Through Registers
Data
Type
Access
Name
USHORT
R/W
Sensor Network
USHORT
R/W
Command/Response string
Default
Value
0
0
7.11.1 Sensor Network
This non-volatile register selects the sensor network for pass-through. Setting this register to zero
disables pass-through communication. The data log must be disabled or paused in order to use passthrough commands.
7.11.2 MODBUS Protocol Pass-Through
If the selected sensor network is configured for a MODBUS protocol, the PWS-600 passes any MODBUS
command on its communication port that is not addressed to the PWS-600 itself to the sensor network,
and will pass back the sensor response. The sensor will appear as if it resides on the master network. If
the MODBUS protocol or communication setting of the sensor network differs from that of the
communication port, the device will translate messages accordingly.
7.11.3 SDI-12 Protocol Pass-Through
If the selected sensor network is configured for the SDI-12 protocol, the master device must utilize the
SDI-12 Command/Response registers and device command to generate a pass-through message and
receive the response.
The command and response string is treated as a packed ASCII STRING data type as described in the
Data Types section of the manual; however individual registers are read/write accessible so that only
the required registers need to be written or read instead of the entire contents of the string.
Use the following procedure to pass an SDI-12 command to a sensor and obtain the response.
1.
Write the packed ASCII command beginning at register 2001. Each register contains two ASCII
characters, with the upper byte of the register holding the leading character. The command
must begin with the SDI-12 address, and end with the “!” character. No other validation of the
command format is performed, allowing sensor-specific extended commands to be sent.
2.
Write device command 56481 to the device command register to send the command to a
sensor on the SDI-12 network. All characters up to and including the “!” character will be sent.
If the “!” character is not found in the string, the command will not be sent.
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3. The Sensor Busy bit in the Device Status register can be monitored to determine when the
command/response cycle is finished. Generally, the response of the SDI-12 sensor is faster than
the sensor busy status can be checked, allowing this step to be skipped.
4. The device returns the sensor response in the command/response string beginning at register
1801. The original command is overwritten. All characters returned by the sensor, up to and
including the carriage return and line feed character are provided. Character positions following
the line feed character are padded with zeroes. If no response is received from the sensor, the
entire string will be filled with zeroes.
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7.12 Password Security Registers
Additional module security is available by enabling password protection. When a security password is
written to the PWS-600, the master device must log in with the correct password in order to access any
of the device registers. When the device is secure, only the read slave id function and the write to the
login password registers are possible.
Data Log Retrieval Registers
Register
Number
3000
3010
Size
(Registers)
10
10
Data
Type
STRING
STRING
Access
W
W
Name
Security Password
Login Password
Default
Value
0
0
7.12.1 Security Password
This ten-register, non-volatile, register string sets the password for the device. By default, the registers
are set to zero, disabling password protection. The device slave id and all device registers are open and
accessible.
Writing a 10-register, non-zero password to these registers enables password security. If no
communication port activity is detected after a period of 60 seconds, or if the Security Mode device
command (56320) is issued, the device will enter its secure mode. In the security mode, only the slave
id and the login password registers are available. Attempting to perform any other function while in the
security mode will result in an exception response with the SECURITY MODE exception code.
Note: It is the responsibility of the user to manage passwords. Once written, the security
password cannot be read out of the device. Once the device is secured with a password, it
cannot be accessed without the original password.
7.12.2 Login Password
Writing a 10-register password that matches the Security Password will temporarily take the device out
of the security mode. Logging in with a password that does not match the security password will result
in an exception response with the ILLEGAL WRITE VALUE exception code and, if the device is in the
security mode, the device will remain in the security mode.
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7.13 Diagnostic Registers
These registers provide device diagnostic and troubleshooting information.
Device Description
Register
Number
9000
9001
9002
9003
9004
9005
9006
9007
Size
(Registers)
1
1
1
1
1
1
1
1
Data
Type
USHORT
USHORT
USHORT
USHORT
USHORT
SHORT
SHORT
USHORT
Access
R
R
R
R
R
R
R
R
9008
1
USHORT
R
Name
Configuration Flash Writes.
Last Reset Type
Fault Count
Last Fault Type
Last Fault Information
High Temperature
Low Temperature
Data Log Chip Id
Data Log Erasure Count
Default
Value
< 50,000
0
0
0
0
°C x 10
°C x 10
8214 or
9538
< 50,000
7.13.1 Configuration Flash Writes
This non-volatile register records the number of times the device configuration registers have been
written to. Since these registers are intended for occasional configuration of the device, a high number
indicates frequent changes and possibly improper use of the registers.
7.13.2 Last Reset Type
This register records information about the last reset event that caused the power outage bit to be set
in the device status register.
Type
0
1
2
3
Reset Types
Description
None recorded
Power outage detected by the CPU – power lost and restored
Brownout detected by CPU – marginal power source (e.g. very low battery)
Brownout detected by the timekeeping circuit – marginal power source
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7.13.3 Fault Information
These registers record information about the last fault event that caused the device fault bit to be set in
the device status register. The fault count records the number of fault events. An occasional fault may
indicate a normal recovery from an unusual power loss sequence or transient event. Frequent faults
may indicate hardware damage or a firmware defect.
Type
0
4
5
6
Fault Types
Description
None recorded
Invalid interrupt, last fault information register updated with interrupt number
Memory access violation
Watchdog timeout
7.13.4 High and Low Temperatures
These registers record the ambient temperature extremes (in degrees Celsius multiplied by 10)
experienced by the device.
7.13.5 Data Log Chip Id
This register reports the identification of the internal data log chip. The value may be any one of the
values listed in the table.
7.13.6 Data Log Erasure Count
This non-volatile register records the number of times the data log has wrapped around and/or has been
erased.
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8 MODBUS Protocol
The PWS-600 utilizes the MODBUS over Serial Line protocol for communication over an RS485 network.
The MODBUS Serial Line protocol is a half-duplex, master-slave protocol. One master device controls
the network or link, and is connected to one or more slave devices. A MODBUS transaction is always
initiated by the master device. Slave devices never transmit data without first receiving a request from
the master device. Slave devices never communicate with each other. The master device only initiates
one MODBUS transaction with one slave device at a time. The PWS-600 implements the functions of a
slave device in the protocol.
The MODBUS standard defines two serial transmission modes: RTU mode and ASCII mode. All devices
connected to a network must be configured to use the same transmission mode and communication
parameters. This device supports both transmission modes.
8.1 RTU Transmission Mode
The MODBUS RTU (Remote Terminal Unit) transmission mode is an 8-bit byte-oriented binary protocol
with timing-based message framing. The RTU mode is the default transmission mode for the device.
8.1.1 RTU Character Format
The standard format for each character in an RTU message is as follows.
1
Start
2
Bit 0
3
Bit 1
4
Bit 2
5
Bit 3
6
Bit 4
7
Bit 5
8
Bit 6
9
Bit 7
10
Parity
11
Stop
The 11-bit character is sent least-significant bit first, left to right as shown, with 1 start bit, 8 data bits, a
parity bit, and one stop bit. The default parity of the device is even parity. Odd parity and no parity are
also supported.
When no parity is specified, 2 stop bits should be used so that the 11-bit character size is maintained:
1
Start
2
Bit 0
3
Bit 1
4
Bit 2
5
Bit 3
6
Bit 4
69
7
Bit 5
8
Bit 6
9
Bit 7
10
Stop
11
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PWS-600 User’s Manual
8.1.2 RTU Message Format
An RTU message is comprised of a sequence of 4 to 256 characters transmitted in a continuous stream.
No more than 1.5 character times should be permitted between the characters in a message. The
format of a message is as follows.
Slave Address
1 byte
Function Code
1 byte
Data
0 to 252 bytes
CRC
2 bytes
By default, for baud rates less than or equal to 19200, an idle time of 3.5 character times signifies the
end of a message. For baud rates higher than 19200, an idle time of 1.75 milliseconds signifies the end
of a message.
The RTU mode uses a Cyclical Redundancy Check (CRC) to provide error checking across a message, from
the slave address to the last data byte. Only the eight data bits of each character are used in generating
the CRC; start and stop bits and the parity bit do not apply. The CRC field is a 16-bit value. The loworder byte is appended first, followed by the high-order byte. The high-order byte of the CRC is the last
byte in the message. A slave device will not act on or respond to a message that has an invalid CRC or
parity errors. The master device must discard a slave response with an invalid CRC or parity errors and
either resend the message or generate an error.
Techniques for calculating the CRC can be found in the document MODBUS over Serial Line Specification
and Implementation Guide V1.02, available at modbus-ida.org.
8.2 ASCII Transmission Mode
In the MODBUS ASCII transmission mode, each 8-bit byte in a message is sent as two hexadecimal ASCII
characters. The message is also framed with unique ASCII characters. This mode is preferred when the
communication link cannot guarantee the inter-character timing required by the RTU mode, such as a
packet-based wireless link.
8.2.1 ASCII Character Format
The standard format for each character in an RTU message is as follows.
1
Start
2
Bit 0
3
Bit 1
4
Bit 2
5
Bit 3
6
Bit 4
7
Bit 5
8
Bit 6
9
Parity
10
Stop
The 10-bit character is sent least-significant bit first, left to right as shown, with 1 start bit, 7 data bits, a
parity bit, and one stop bit. The default parity of the device is even parity; odd parity and no parity are
also supported.
When no parity is specified, 2 stop bits should be used so that the 10-bit character size is maintained:
1
Start
2
Bit 0
3
Bit 1
4
Bit 2
5
Bit 3
6
Bit 4
70
7
Bit 5
8
Bit 6
9
Stop
10
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PWS-600 User’s Manual
Although not specified by the MODBUS standard, the PWS-600 will also support the ASCII mode using 8bit characters with or without parity as described for the RTU mode.
8.2.2 ASCII Message Format
An ASCII message is comprised of a sequence of 9 to 513 characters. The format of a message is as
follows.
Start
1 char ‘:’
Slave Address
2 chars
(1 byte)
Function Code
2 chars
(1 byte)
Data
0 to 504 chars
(0 to 254 bytes)
LRC
2 chars
End
2 chars CR, LF
The ASCII colon character “:” begins a message. The message ends with the ASCII control characters
carriage return (CR) and line feed (LF). The byte information of an ASCII message from the slave address
to the end of the data is identical to that of an RTU message. Each byte of the message is transmitted as
two ASCII hexadecimal characters 0-9, A-F.
By default, intervals up to one second may elapse between characters within the message. The device
supports a programmable timeout interval up to 60 seconds. Intervals exceeding the timeout value will
cause the device to assume an error has occurred and discard the message. Each reception of a colon
character signals the beginning of a new message. If a message was in the process of being received
when a colon is received, the previous message will be discarded.
The ASCII mode uses a Longitudinal Redundancy Check (LRC) to provide error checking across a
message, from the slave address to the last data byte. The beginning colon and ending CR-LF pair are
not included in the calculation. Only the data bits of each character are used in generating the LRC; start
and stop bits and the parity bit do not apply. The LRC is an 8-bit value, encoded with two ASCII
characters in the same manner as a data byte. A slave device will not act on or respond to a message
that has an invalid LRC or parity errors. The master device must discard a slave response with an invalid
LRC or parity errors and either resend the message or generate an error.
Techniques for calculating the LRC can be found in the document MODBUS over Serial Line Specification
and Implementation Guide V1.02, available at modbus-ida.org.
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8.3 MODBUS IP
This device also supports the MODBUS IP protocol on its master-side RS485 port. It is provided to
support cases where a companion gateway or modem does not support translation between MODBUS
IP and either MODBUS RTU or MODBUS ASCII. An IP message is essentially a MODBUS RTU message
with an extended header.
Transaction Id
2 bytes
Protocol Id
2 bytes
Length
2 bytes
Slave Address
1 byte
Function Code
1 byte
Data
0 to 252 bytes
The transaction id identifies a MODBUS command/response transaction. It is uniquely set by the master
device and echoed by the slave device.
The protocol id specifies the transaction protocol. It must always be set to zero to specify MODBUS.
The length field specifies the length of the remaining bytes in the packet, including the slave address,
function code, and data.
8.4 Device Addressing
The MODBUS master device has no specific address, only the slave devices have an address. Each slave
device on a network must be assigned a unique address. Slave addresses can range from 1 to 247.
Address 0 is reserved as the broadcast address. The device will recognize the broadcast address as well
as its own address. No response is returned to broadcast requests.
8.5 Data Types
The MODBUS Protocol defines four primary data models: Discrete Inputs, Coils, Input Registers, and
Holding Registers. The PWS-600 uses the Holding Registers model exclusively.
MODBUS uses big endian representation for register numbers and data items – when a numerical
quantity larger than a single byte is transmitted, the most significant byte is sent first. Register data are
packed as two bytes per register, the first byte contains the high order bits and the second byte contains
the low order bits.
The device extends the big endian representation to data types requiring multiple registers. The first
register contains the high order bytes and subsequent registers contain the lower order bytes.
8.5.1 USHORT: Unsigned Short
An unsigned short is a 16-bit unsigned integer value in the range 0 to 65535. The value is contained in a
single register. This is the basic MODBUS holding register data type.
Register
Byte 1
Bits 15 - 8
Byte 2
Bits 7 - 0
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8.5.2 SHORT: Signed Short
A signed short is a 16-bit two’s complement signed integer value in the range -32768 to +32767. The
value is contained in a single register.
Register
Byte 1
Sign, Bits 14 - 8
Byte 2
Bits 7 - 0
8.5.3 ULONG: Unsigned Long
An unsigned long is a 32-bit unsigned integer value contained in two consecutive registers. Values can
range from 0 to 4,294,967,295.
Register
Byte 1
Bits 31 - 24
Register + 1
Byte 2
Bits 23 - 16
Byte 3
Bits 15 - 8
Byte 4
Bits 7 - 0
8.5.4 LONG: Signed Long
A signed long is a 32-bit two’s complement signed integer value contained in two consecutive registers.
Values can range from -2147483648 to +2147483647.
Register
Byte 1
Sign, Bits 30 - 24
Register + 1
Byte 2
Bits 23 - 16
Byte 3
Bits 15 - 8
Byte 4
Bits 7 - 0
8.5.5 FLOAT: Floating Point
A float is a 32-bit IEEE-754 floating point value contained in two consecutive registers.
Register
Byte 1
SXXXXXXX
Register + 1
Byte 3
Byte 4
MMMMMMMM
MMMMMMMM
Byte 2
XMMMMMMM
S is the sign bit, X is the 8-bit exponent, and M is the 23-bit mantissa.
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8.5.6 STRING: Character String
A string is a sequence of consecutive registers where each byte within a register represents an 8-bit
ASCII-encoded character. A string of N characters requires N / 2 registers. When reading or writing a
string, all characters in the string must be transmitted. If the string to be written does not require the
full available length, the unused characters must be padded with zeroes.
Register
Byte 1
Character 1
Byte 2
Character 2
Register + 1
Byte 1
Character 3
Byte 2
Character 4
.
.
.
Register + (N / 2) – 1
Byte 1
Byte 2
Character N - 1
Character N
8.5.7 TIME: Date and Time
Time is represented by 16 packed BCD digits contained in 4 consecutive registers. The registers are
organized with the most significant temporal digit first, ranging from 1000 years to 0.01 seconds. Only
BCD digits ‘0’ to ‘9’ are used. Time is in the 24-hour format.
Register
Byte 1
1000 years
100 years
Byte 2
10 years
Year
Register + 1
Byte 1
10 Months
Month
Byte 2
10 Days
Day
Register + 2
Byte 1
10 Hours
Byte 2
10 Minutes
Minutes
Hour
Register + 3
Byte 1
Byte 2
10 Seconds
Seconds
0.1 Seconds
0.01 Seconds
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8.6 Function Codes
The MODBUS Protocol defines a variety of standard function codes for reading and writing data to a
device. Only the function codes described in this section are supported by the device. All other function
codes will generate an exception response with the ILLEGAL FUNCTION exception code.
8.6.1 Report Slave Id
This function code is used to read the device description. All of the device-specific information is also
available in the register map and is detailed in that section.
Byte Offset
0
1
Command
Field Description
Device Address
Function Code
Byte Offset
0
1
2
3
4
5
7
9
13
15
17
19
Field Description
Device Address
Function Code
Byte Count
Slave Id
Run Status Indicator
Slave Id Version
Device Id
Serial Number
Firmware Version
Boot Code Version
Hardware Version
Register Map Version
Type
BYTE
BYTE
Value
1-247
17 (0x11)
Type
BYTE
BYTE
BYTE
BYTE
BYTE
USHORT
USHORT
ULONG
USHORT
USHORT
USHORT
USHORT
Value
1-247
17 (0x11)
18
80 (0x50) ‘P’
255 (0xFF) = ON
1
600
Response
The response to a slave id command is typically returned in less than 50 milliseconds.
8.6.2 Read Registers
This function code is used to read the contents of a contiguous block of registers.
Byte Offset
0
1
2-3
4-5
6
7
Command
Field Description
Device Address
Function Code
Starting Register Address
Number of Registers (N)
CRC Low
CRC High
75
Type
BYTE
BYTE
USHORT
USHORT
BYTE
BYTE
Value
1-247
3 (0x03)
0-65535 (0xFFFF)
1-125 (0x007D)
PWS-600 User’s Manual
Response
Byte Offset
0
1
2
3
Field Description
Device Address
Function Code
Byte Count
Register Data
Type
BYTE
BYTE
BYTE
2 x N BYTES
Value
1-247
3 (0x03)
2xN
The starting register address is one less than the starting register number. The byte count returned will
be two times the number of registers read.

If the Read Registers function code is used to read data from a single register, the single register
must be a single-register data type such as a USHORT. An attempt to read a single register from
within a multiple-register data type will result in an exception response with the ILLEGAL DATA
ADDRESS exception code.

If the Read Registers function code is used to read a multiple-register data type, the start
register address must be of the first register in the field and the number of registers must
include all registers in the field. If one or both parameters are invalid, the device will return an
exception response with the ILLEGAL DATA ADDRESS exception code.

The Read Registers function code can be used to read data from multiple registers of the same
or different data types. In this case, the starting register address must be of either a singleregister data type or the first register in a multiple-register data type. The last register read
must be either a single-register data type or the last register in a multiple-register data type.
Attempting to start or end the read within a multiple-register data type will result in an
exception response with the ILLEGAL DATA ADDRESS exception code.

Some registers are designated as write-only (W versus R/W in the register map). Attempting to
read a write-only register, the device will result in an exception response with the WRITE-ONLY
REGISTER exception code.
The response to a read registers command is typically returned in less than 50 milliseconds.
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8.6.3 Write Multiple Registers
This function code is used to write the contents of a contiguous block of registers.
Byte Offset
0
1
2
4
6
7
Command
Field Description
Type
Device Address
BYTE
Function Code
BYTE
Starting Register Address
USHORT
Number of Registers (N)
USHORT
Byte Count
BYTE
Register Data
2 x N BYTES
Byte Offset
0
1
2
4
Field Description
Device Address
Function Code
Starting Register Address
Number of Registers
Value
1-247
16 (0x10)
0-65535 (0xFFFF)
1-123 (0x007B)
2xN
Response
Type
BYTE
BYTE
USHORT
USHORT
Value
1-247
16 (0x10)
0-65535 (0xFFFF)
N
The starting register address is one less than the starting register number. The byte count must be two
times the number of registers to be written.

If the Write Multiple Registers function code is used to write data to a single register, the
register must be a single-register data type such as a USHORT. An attempt to write a single
register within a multiple-register data type will result in an exception response with the
ILLEGAL DATA ADDRESS exception code.

If the Write Multiple Registers function code is used to write a multiple-register data type, the
start register address must be of the first register in the field and the number of registers must
include all registers in the field. If one or both parameters are invalid, the device will return an
exception response with the ILLEGAL DATA ADDRESS exception code.

The Write Multiple Registers function code can be used to write data to multiple registers of the
same or different data types. In this case, the starting register address must be of either a
single-register data type or the first register in a multiple-register data type. The last register
written must be either a single-register data type or the last register in a multiple-register data
type. Attempting to start or end the write within a multiple-register data type will result in an
exception response with the ILLEGAL DATA ADDRESS exception code.

Some registers are designated as read-only (R versus R/W in the register map). Attempting to
write data to a read-only register will result in an exception response with the READ-ONLY
REGISTER exception code.
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
If an attempt is made to write an out-of-range value to a register, an exception response with
the ILLEGAL WRITE VALUE exception code will be returned.

If the function returns an exception response with an exception code of ILLEGAL DATA ADDRESS
or READ-ONLY REGISTER, no data was written to any of the registers.

If the function returns an exception response with an exception code of ILLEGAL WRITE VALUE
or DEVICE FAILURE, data was written to registers up to but not including the register that caused
the exception. No data was written to registers after the register that caused the exception.
There is no provision in the exception response to isolate the problem register.
The response to a write multiple registers command is typically returned in less than 100 milliseconds.
8.6.4 Write Single Register
This function code is used to write the contents of a single register. Only single-register data types can
be written with this function. Writing to a multiple-register data type requires the Write Multiple
Registers function code.
Byte Offset
0
1
2
4
Command
Field Description
Device Address
Function Code
Register Address
Register Data
Type
BYTE
BYTE
USHORT
USHORT
Value
1-247
6 (0x06)
0-65535 (0xFFFF)
0-65535 (0xFFFF)
Type
BYTE
BYTE
USHORT
USHORT
Value
1-247
6 (0x06)
0-65535 (0xFFFF)
0-65535 (0xFFFF)
Response
Byte Offset
0
1
2
4
Field Description
Device Address
Function Code
Register Address
Register Data
The register address is one less than the register number.

An attempt to write a single register within a multiple-register data type will result in an
exception response with the ILLEGAL DATA ADDRESS exception code.

Some registers are designated as read-only (R versus R/W in the register map). Attempting to
write data to a read-only register will result in an exception response with the READ-ONLY
REGISTER exception code.

If an attempt is made to write an out-of-range value to a register, an exception response with
the ILLEGAL WRITE VALUE exception code will be returned.
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The response to a write single register command is typically returned in less than 100 milliseconds.
8.6.5 Exception Response
When the device encounters an error condition in a command from the Master, it will reply to the
command with the standard MODBUS exception response.
Byte Offset
0
1
2
Exception Response
Field Description
Type
Device Address
BYTE
Function Code + 128 (0x80)
BYTE
Exception Code
BYTE
Value
1-247
128-255 (0x80-0xFF)
0-255 (0xFF)
8.6.5.1 Standard Exception Codes
The following exception codes are defined by the MODBUS protocol.
Exception Code
1 (0x01)
Name
ILLEGAL FUNCTION
2 (0X02)
ILLEGAL DATA ADDRESS
3 (0x03)
ILLEGAL DATA VALUE
4 (0x04)
DEVICE FAILURE
10 (0x0A)
GATEWAY PATH
UNAVAILABLE
Description
The function code received in the command is not
valid for the device.
The register address or the register range received in
the command is not valid.
A value contained in the command is not valid, such
as a mismatch between the number of registers and
the byte count. This exception indicates an error in
the structure of a command.
An error occurred in the device while attempting to
perform the command.
An attempt was made to use pass-through
communication while data logging is enabled.
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PWS-600 User’s Manual
8.6.5.2 Custom Exception Codes
The following exception codes are device-specific extensions to the standard codes to help speed
command/response troubleshooting.
Exception Code
128 (0x80)
Name
READ-ONLY REGISTER
129 (0x81)
WRITE-ONLY REGISTER
130 (0x82)
ILLEGAL WRITE VALUE
131 (0x83)
132 (0x84)
133 (0x85)
CORRUPT DATA RECORD
DOWNLOAD END
SECURITY MODE
Description
The command attempted to write data to a readonly register.
The command attempted to read data from a writeonly register.
The command attempted to write an illegal or out of
bounds value.
The requested data record is corrupted.
End of fast data log download.
The requested function is not available in security
mode.
80